ISSN : 2277-1328 (Online) - ISRM

ISSN : 2277-131X (Print) 

ISSN : 2277-1328 (Online) 

ISRM 

 

(India) 

Vol. 1, No. 2 - July 2012 

Half Yearly Technical Journal of Indian National Group of ISRM

AIMS AND SCOPE 

ISRM (India) Journal is a half yearly journal of the Indian National Group of International Society for 

Rock Mechanics (ISRM), which is involved in dissemination of information on rock mechanics, and its 

related activities in the field of foundation and abutments of dams, tunnel engineering, mining, underground 

works, rock slope stability, road works, etc. 

The aim of the journal is to encourage exchange of ideas and information between rock mechanics 

practitioners worldwide. The journal provides an information service to all concerned with Rock Mechanics 

about the development of techniques, new trends, experience gained by others to enable updating of 

knowledge. The original manuscripts that enhance the level of research and contribute new developments 

to the Rock Mechanics are encouraged. The journal is expected to exchange ideas and information 

between Rock Mechanics practitioners, help researchers, technologist and policy makers in the key 

sector of Water Resources, Infrastructure Development (including underground works), Hydro Power, 

Mining and Petroleum Engineering, etc. to enhance their understanding of it. The Journal has both print 

and online versions. Being peer-reviewed, the journal publishes original research reports, review papers 

and communications screened by the Editorial Board, consisting of renowned experts. 

The manuscripts must be unpublished and should not have been submitted for publication elsewhere. 

There are no Publication Charges. 

EDITORIAL BOARD 

• Dr. David Beck, Beck Engineering, AUSTRALIA 

• Dr. A.K. Dhawan, Chief Consultant, Fugro Geotech Ltd. and Former Director, Central Soil and 

Materials Research Station, INDIA 

• Prof. Xia-Ting Feng, Institute of Rock and Soil Mechanics, The Chinese Academy of Sciences, 

CHINA 

• Dr. Abdolhadi Ghazvinian, Department of Mining Engineering, Faculty of Engineering, Tarbiat- 

Modares University, IRAN 

• Dr. R.K. Goel, Chief Scientist, Central Institute of Mining and Fuel Research, Regional Centre, 

Roorkee, INDIA 

• Dr. Luis Lamas, Secretary General, ISRM and Head of the Foundations and Underground Works 

Division, Portuguese National Laboratory of Civil Engineering, PORTUGAL 

• Dr. A. Nanda, Deputy General Manager, Engineers India Limited, Sub Surface Projects Division, 

INDIA 

• Dr. H.R. Sharma, Director – Design and Engineering, GVK Technical & Consultancy Services Pvt. 

Ltd., INDIA 

• Dr. K.G. Sharma, Professor, Department of Civil Engineering, Indian Institute of Technology Delhi, 

INDIA 

• Dr. Antonio Samaniego, Principal Lecturer (Rock Mechanics), Catholic University of Peru, PERU 

• Dr. Yingxin Zhou, Defence Science & Technology Agency, SINGAPORE

INDIAN NATIONAL GROUP OF ISRM 

ISRM (INDIA) JOURNAL 

Volume 1, No. 2 July 2012 

CONTENTS 

Page No. 

FROM EDITOR’S DESK 2 

• Supporting Collapsed and Highly Deformed Areas of Block Cave Extraction Levels - 

D. Beck and E. Villaescusa 3 

• Study of Wellbore Stresses and Stability Based on a Hollow Cylinder Model – 

P.A. Nawrocki, Z. Qi and D. Wang 10 

• Engineering Geological and Geotechnical Evaluation of Dam Spillway (II-C) of Bunakha 

Hydroelectric Project, Bhutan Himalaya – 

A.K. Naithani, L.G. Singh, Devendra Singh Rawat and P.C. Nawani 16 

Governing Council for the Term 2011-2014 23 

Recent Activities of Indian National Group 

• Seminar on “Geotechnical Challenges in Water Resources Projects” 19-20 January 2012, 

Dehradun (Uttarakhand) 24 

• International Seminar on “Survey and Investigations of Hydroelectric Projects – Issues and 

Challenges” 28th March 2012, New Delhi 25 

• Seminar on Issues in Appraisal of Detailed Project Reports of Hydroelectric Projects – 

22 June 2012, New Delhi 26 

ISRM News 28 

Publications of Indian National Group 32 

ISRM Sponsored Forthcoming Events 33 

Guidelines for Authors 35 

All communications to be addressed to : 

The Member Secretary 

Indian National Group of ISRM 

CBIP Building, Malcha Marg, Chanakyapuri, New Delhi – 110 021 

Subscription Information 2012/ (2 issues) 

Institutional subscription (Print & Online) 

Institutional subscription (Online only) 

Institutional subscription (Print Only) 

: Rs. 900/US$75 

: Rs. 600/US$50 

: Rs. 600/US$50 

Volume 1 No. 2 July 2012

2 ISRM (India) Journal 

FROM THE EDITOR’S DESK 

I thank all the readers of the inaugural issue of the journal for their feedback about 

the journal. The feeback from all the quarters has given us the encouragement to 

our initiative and to bring out a quality journal. 

The Society initiated its activities with a Seminar on "Geotechnical Challenges in 

Water Resources Projects" in January 2012 in Dehradun. The objective of the 

proposed Seminar was to provide a forum for the design and construction engineers 

to discuss the solutions to various geological and geotechnical surprises 

encountered during the execution of various River Valley Projects and use the 

knowledge for safe and economical design and construction of such projects. There 

was participation from 26 organisations, including from Bhutan, in the Seminar. 

The activities planned during the second half of the year, include Seminars on "Ground Control and 

Improvement", in September 2012 and "Slope Stabilization Challenges in Infrastructure Projects" in 

November 2012. The objectives of the proposed Seminar are to provide a forum for the design and 

construction engineers to discuss the potentially applicable ground improvement methods for civil 

works structures and the solutions to various geological and geotechnical surprises encountered during 

the execution of various River Valley Projects and use the knowledge for safe and economical design 

and construction of such projects. 

From the year 2013, the Society has planned for one major activity on Rock Mechanics to be held 

annually, in addition to other courses and workshops on the subject. The first national event is planned 

shortly. The formal announcement will be made soon. 

I thank all the authors for their contributions to this issue. I thank the members of the Editorial Board for 

sparing their valuable time to review the papers and offer their comments/suggestions to improve the 

contents of the articles. 

One of the suggestions received from the readers of the journal is to take up more case studies related 

contributions. I request all the readers and their colleagues/fellow professionals to contribute the case 

studies to further improve the utility of the Journal. 

V.K. Kanjlia 

Member Secretary 



3 

SUPPORTING COLLAPSED AND HIGHLY DEFORMED 

AREAS OF BLOCK CAVE EXTRACTION LEVELS 

D. Beck E. Villaescusa 

Beck Engineering Pty Ltd, Australia 

CRC Mining, Australia 

ABSTRACT 

Large deformations in deep mines occur due to the exposure of extensively damaged rock mass adjacent 

to an excavation. In order to properly simulate the support response in such conditions, the ground 

deformation must be captured accurately. The mechanisms of rock mass damage, dilation and deterioration 

must first be correctly simulated to produce a realistic tunnel deformation in three dimensions. Furthermore, 

the physical response of the support elements must be realistic. 

In this paper, a multi-scale approach to mine deformation modelling has been described to improve the 

simulation similitude of ground support capacity and demand. Case studies were used to demonstrate the 

behaviour of several heavy support systems using this approach. Some support designs for squeezing 

ground were tested and the limitations and vulnerabilities of the support systems described. The modelling 

methods used to simulate the mine deformation, drive behaviour and support system response were 

discussed and some sufficiency requirements for similar analysis were highlighted. 

1. INTRODUCTION 

The purpose of ground support is to ensure that 

excavations remain safe and open for their intended life 

span. The effectiveness of a ground support strategy is 

important for two main reasons, namely safety to personnel 

and equipment and to achieve the most economical 

access to extract ore. Ground support consists of rock 

support and rock reinforcement (Windsor & Thompson, 

1993) which is installed into a deformed, discontinuous 

rock mass. The loads that develop in the support system 

are a function of displacement and distortion due to 

damage in the rock mass and the resultant forces 

generated by blocks and wedges that would otherwise be 

kinematically free to fall or slide into the excavation (Beck 

et al, 2010). 

To evaluate the likely performance and behaviour of a 

support system, the evolution and timing of the 

discontinuous deformation within a rock mass must be 

captured. This is a complex problem - if the simulated 

‘loading system’ displacements, or the simulated support 

system load-displacement response is incorrect, the 

evaluation will not be sufficient. 

2. CAUSES OF SIGNIFICANT EXTRACTION LEVEL 

DEFORMATION 

Deformation in undercut and extraction level development 

occurs in stages. Damage to the walls of excavations 

prior to extreme closure can be significant but is usually 

managed with modest support or rehabilitation, while 

extreme damage - drive closure and collapse - occurs 

when pillar cores fail. Pillar core failure is the most extreme 

case of extraction level collapse, as opposed to damage 

and differentiates ‘normal’ caving ground control problems 

from extreme failure. 

By definition, pillar instability is reached when the strain 

in the pillar core reaches a critical level, either due to 

failure of the rock mass in the pillar or due to yield and 

dislocation of structure. The effect is the same; at the 

critical level of strain in the pillar core, pillar deformation 

will continue to occur at constant (or reducing) stress. 

Large scale structures contribute by either weakening the 

pillar or by concentrating loads in susceptible areas of 

the footprint. 

Interpreting pillar core conditions using plastic strain is 

consistent with standard geotechnical practice. 

Conventional theorems of plastic collapse for limit analysis 

are well documented (Yu, 2006; Hodge, 1958; Davis, 1968; 

Lubliner, 1990; Drucker et al., 1952; Hill, 1951). The only 

possible interpretation of significant plastic strain in pillar 

cores is pillar collapse, while moderate plastic strain should 

be associated with a step change in adjacent tunnel 

deformation if not collapse. 

For block caves, the estimation of pillar core damage is 

complex. The extraction horizon is a closely coupled 

system of small, diamond shaped pillars - a heavily 

extracted slice 4-5 or so metres high within which virtually 

all of the vertical cave loads acting at the base of the 

cave must be carried and an equilibrium attained. An 

example relation between crosscut spacing and extraction 

ratio (assuming all other dimensions are fixed) for a 

particular block cave extraction level design is shown in 

Figure 1. As crosscut spacing decreases, the extraction 

3 



ratio, and therefore the material retained to bear cave loads 

changes almost exponentially. 

Fig. 1 : An example relation between crosscut spacing and 

extraction ratio (assuming all other dimensions are fixed) 

for a particular block cave extraction level design 

The capacity of this ‘system’ of pillars is further diminished 

by many factors. For deep caves critical considerations 

include: 

• Scale effects; the pillar scale strength is a small fraction 

of the laboratory scale strength, probably closer to 

the rock mass strength for most jointed rocks suitable 

for caving. 

• The very high extraction ratio. This well understood, 

but sometimes not fully accounted for. Many models 

do not simulate the extraction level excavations, 

instead using an ‘equivalent material’ approach that 

approximates the presence of extraction level tunnels 

using a softer material for the entire horizon. The 

problem with this approach is that it cannot account 

for the loss of confinement that occurs when the 

drawpoints and drawbells are mined nor the real impact 

on pillar loads. As the confinement is much reduced, 

so too is the strength of pillars even if there is no prior 

damage and if this is not recognised the capacity of 

the extraction level to bear load will be overestimated. 

At even minor levels of rock mass damage (i.e., prepeak) 

induced on the extraction level during 

undercutting,the effects of the reduction in confinement 

when drawpoints are extracted will be observable. 

• The centroid between extraction level crosscuts is not 

the location of the most important extraction level 

pillars cores. The real extraction level drawpoint pillar 

centroid is infact just a few metres from the extraction 

level crosscut, within the zone of influence of the 

extraction level crosscut if it is already in place as the 

undercut is mined. 

• Damage at the walls of pillars acts to diminish the 

‘effective’ area of the pillar even though the ‘future’ 

pillar core may experience only minor or no damage. 

Poorly conditioned models with an inadequate type or 

insufficient number of elements will not capture this 

effect, nor will models with over-sized extraction steps. 

The most subtle of all of these points may be the loss of 

confinement that occurs on the extraction level when the 

drawpoints and drawbells are mined. It can explain why 

cave loads can still affect pillars which show only minor 

or moderate damage prior to extraction of the drawbells. 

The reason for the initial lack of damage (i.e., in advance 

of the undercut), will usually be the positive effects of 

confinement up until this point and the large crosscut 

spacing. Once the undercut has passed and drawbells 

and drawpoints are extracted, the loss of confinement 

can leads to an immediate loss in capacity. Since the 

cave loads havenot developed at that time, this capacity 

reduction may not even be noticed. 

Too often it is assumed that as the peak strength has not 

been exceeded prior to undercutting that the same confined 

triaxial strength remains after drawbell and drawpoint 

extraction, but the loss of confinement means that the 

effective capacity of a pillar from that point forward will be 

much reduced, apart from the effects of the very high 

extraction ratio. 

The effect of both combined is a step change reduction in 

capacity of the horizon to bear loads after the draw points 

and draw bells are extracted; the pillars are essentially, 

or almost only uniaxially loaded from that point on and 

the strength of a pillar, or its capacity can be halved or 

more even though it has been ‘destressed’ by undercutting 

and even though the rock is not in a residual state. 

These considerations lead to several pillar scenarios that 

must therefore be considered in any deep block cave: 

• Low deformation should be expected where the rock 

mass is sufficiently strong, only very minor or no 

damage develops on the extraction horizon before the 

undercut has passed, and the subsequent drop in 

confinement and loss of capacity (when the 

construction is completed) is small enough that future 

cave loads will be managed despite the high extraction 

ratio. The key positive factors are low enough cave 

load, the extraction ratio and the peak rock mass scale 

compressive strength. 

• Higher deformation should be expected at low enough 

strengths, or high enough abutment stresses, 

thatdamage on the extraction level at future pillar core 

locations occur during undercutting. The subsequent 

losses of confinement and the increasing extraction 

ratio does sufficiently reduce the capacity of the 

extraction horizon to bear future cave loads.The actual 

cave loads will determine the final state of damage. 

• In some circumstances, the rock may be so weak 

that it is damaged sufficiently at the abutment that a 


Supporting Collapsed and Highly Deformed Areas of Block Cave Extraction Levels 

5 

residual strength, or something closer to it is attained. 

Relatively low cave loads will cause large amounts 

further damage. 

3. AN EXAMPLE PROCEDURE FOR SIMULATING 

SUPPORT CAPACITY AND DEMAND FOR BLOCK 

CAVING MINES (AFTER BECK ET AL 2010) 

Beck et al (2010) outline fundamental sufficiency 

requirements for properly simulating deformation on 

extraction levels and undercuts of block caves. In 

summary: 

• Generally, displacement realistic models will usually 

be 3D. 

• Capturing the geometry of a problem is essential to 

simulate the stress path and this means not only 

representing the shape of excavations and structure, 

but also simulating the timing and the excavation 

process. 

• Assuming a sufficient type and density of elements is 

used and the analytical framework can solve for the 

physical response that needs to be captured, the 

practical challenge for ground support problems is to 

simulate the continuous and discontinuous parts of 

the deformation field around a drive. This implies that 

the model will capture the stress strain behaviour well 

enough to model the extent and magnitude of damage 

around the excavation (for example with a strainsoftening, 

dilatant, large strain model), but also 

incorporate sufficiently small scale structure so that 

the discontinuous deformation and kinematics of the 

problem are captured. 

• The behaviour at many length scales, and the 

interconnectedness between different length scales 

(tunnel, pillar precinct, block and mine) must be 

captured. Deformation and damage at each length 

scale must built upon to simulate successively larger 

length scales and this should be achieved by 

incorporating geometry and sequencing details at a 

resolution and complexity suiting the smallest length 

scale of interest in the problem, but inside a model 

with similar complexity at longer length scales or using 

appropriate sub modeling techniques. 

At this time, it is not efficient to build a single mine-scale 

model with all scales of necessary structure from 

development (drive) scale to global (mine scale). Instead, 

a multi-scale sub-modelling approach can be adopted, 

using larger scale (global)models to provide boundary node 

displacements for smaller scale (sub) models, each with 

successively smaller scale details (see for example Beck 

2008 and Beck et al 2009). 

A simple example of donor and sub models is shown in 

Figure 2 after Beck et al (2010). The purpose of this model 

was to evaluate the capacities of the steel arches and 

steel sets for block caving drawpoint support. A global 

model of the entire mine was used to drive the boundaries 

of a 1/10 footprint sub model spanning from below the 

extraction level to above the undercut. Because many 

support designs needed to be tested, the drives within 

the 1/10 footprint sub model were only filled with supporting 

‘filler’ elements approximating the pre-failure stiffness of 

the systems that were being studied. The displacements 

at the drive surface could then be applied to the explicit 

models of the support elements or directly compared to 

published load-displacement data (Villaescusa, et al, 

1992). In more detailed studies, the support can be 

included directly in the 1/10 footprint model, in order to 

achieve the required resolution of discontinuities. 

In this particular example, the 1/10 footprint models 

incorporate Discrete Fracture Networks (DFN) to represent 

drive scale structure. The included discontinuities are 

shown in the sub model plots. The DFN are based on a 

statistical representation of the discontinuity spatial 

distribution, as outlined in Beck et al (2010). 

The results for excavation closure from this model at an 

isolated location in which large deformation leads to high 

Fig. 2 : Example sections through a 1/10 footprint DFN and 

global donor model used to produce drive surface 

displacements to test steel arch and steel set support. Only 

part of the model is shown. 



drive closure are plotted in Figure 3. This shows 

representative, underlying inwards wall movement versus 

model step in the 1/10 footprint sub model at 3 key 

locations in the sub model; a drawpoint, crosscut and 

drawpoint intersection. Note that the specific location was 

selected in the basis of expected large deformation and 

that the model is calibrated using measured drive closure. 

Almost all of the rest of the footprint shows much lower 

expected drive closure. The model indicates that at this 

selected location, with effective TH or universal beam 

support, up to 255-300 mm of closure is eventually 

expected after propagation of the cave. 

At this level of deformation, damage to steel sets is 

possible, depending on the quality of the installation and 

the specific design. A common steel set design for block 

caves is shown in Figures 4 and 5, also after Beck et al 

(2010). This design is a modification to a design employed 

by a number of block caves around the world, except in 

this design modified concrete and a circular tunnel shape 

are employed. 

A key observation is that significant ground movement is 

required for substantial load to be taken up. Following 

this stage, a large disparity in stiffness between the areas 

of drive affected by the sets and the spans in between is 

experienced. This effect can be seen in Figure 5(i) which 

shows the pattern of radial pressure between the wall of 

the drive and the support system. The support pressures 

generated are much higher adjacent to the sets than they 

are in the spans between, suggesting closer spacing is 

needed for at least this application. The Figure also shows 

the pressure generated by the sets compared to the 

deformation at selected locations around and in-line with 

the square sets (Figure 6(ii)) i.e., at the shoulder and grade 

line, immediately adjacent to one of the sets. The sets 

‘point load’ resulting in massive pressures at certain points, 

and at between 250 mm and 325 mm of closure at the 

brow, the model showed the single steel set starts to buckle 

by a characteristic mechanism near a shoulder (Figure 7, 

comparing set damage from one mine and a close view of 

the modelled buckling is shown in Figure). There is also 

significant concrete damage in areas including the apron 

along the footings of the arch before this owing to the 

pattern of loading of the support system. 

Fig. 3 : Simulated closure at selected locations in the 

example front cave (after Beck et al 2010) 

Fig. 4 : A common steel set design for block cave 

drawpoints 

Fig. 5 : Simulated point loads versus radial deflection for the steel set design. These are not the 

average radial support pressures. 



7 

Fig. 6 : Example of steel set failure, and a close view of steel set failure in the model 

An alternative design could involve high capacity yielding 

elements such as TH arches. A TH arch design is shown 

in Figure 7. It is a moderate to high capacity design 

specified for high levels of drive closure. 

Features of the particular design included ovoid walls and 

back, but a compromised flat floor. In this case, the model 

uses drive deformation information from a real scenario 

observed at a mine where significant tunnel collapses 

occurred due to pillar failures, but where TH arches were 

not used. A conclusion from the analysis was that the TH 

arches helped maintain the drive profile for longer than 

when bolt, mesh and fibrecrete were used, but when the 

cores of adjacent pillars failed the TH arches were not a 

significant constraint on final deformation. 

The conclusion remains the same: excavation shape is 

critical and appropriate design of pillars to manage loads 

is ultimately the essential requirement for stability. 

Another use for these models is to better understand the 

mechanism for the high levels of damage. Results for 

rock mass damage - interpreted using plastic strain - 

through the drawpoint pillars, minor apex and in the walls 

and back at selected sections of the sub model 

excavations are shown at 2 milestones in Figure 8: (a) 

minor to moderate pillar core damage (b) significant pillar 

core damage. 

The detailed modelling correlates drive closure and pillar 

core stability for the example application. Although the 

actual level of closure compared to the pillar damage is 

specific to the rock type and configuration of the 

excavations, the correlation between stability in general 

and with levels of plastic strain should be more transferrable: 

• Pillar cores with significant damage should be 

interpreted as failed. The adjacent excavations will 

also be deformed. From a support perspective these 

drives are candidates for heavy support and planned 

rehabilitation. 

• Pillar cores with moderate damage should be marginal 

- some will be interpreted as failed. In these pillars 

degradation of pillar strength has increased, but the 

actual deformation is still only moderate. The adjacent 

drives should not be significantly deformed, though 

additional load will lead to increased damage and 

deformation in the pillar and adjacent excavations. 

• Pillar cores with minor damage should be expected to 

be stable. Calibration suggests that at this level of 

damage, the rock mass is starting to yield, but a 

significant degradation in strength has not occurred. 

Also, as the deformation is low, deformation in 

adjacent excavations will also be low and heavy 

support is not indicated. 

(i) Moderate Capacity TH support design 

(ii) Failure analysis 



(iii) Photograph of actual deformation in tunnel used to provide load-deformation scenario for failure analysis 

Fig. 7 : Simulated and observed deformation for a compromised TH Arch design 

Fig. 8 : Simulated pillar rock mass damage at selected stages of extraction in an example 1/10 mine scale 

FE DFN model, after Beck et al (2010) 



9 

5. CONCLUSIONS 

The intent of ground support capacity and demand 

modeling is to capture the mechanisms of discontinuous 

deformation around complex geometries with the highest 

possible level of confidence. The magnitudes and extent 

of the deformation in the case examples was calibrated 

using field data, but even without calibration the selection 

of an appropriate support capacity should be possible. 

The common features of sufficient simulation are 

appropriate strain-softening dilatant constitutive models, 

inclusion of small scale discontinuities, higher order 

elements and fine meshes, small excavation steps and 

appropriate boundary conditions. Modern non-linear, strain 

softening, dilatancy model packages allow for computation 

of models such as these in sufficiently short time frames 

and at a cost that makes the analysis feasible. 

REFERENCES 

Beck, D. A. 2008.Multi-scale, non-linear numerical analysis 

of mining induced deformation.In Proceedings of the 42nd 

US Rock Mechanics Symposium and 2nd U.S.-Canada 

Rock Mechanics Symposium, held in San Francisco, June 

29-July 2, 2008. ARMA, American Rock Mechanics 

Association 

Beck, D. A. Reusch, F. 2009.A numerical investigation 

of scale effects on the behavior of discontinuous rock. In 

Proceedings of the 43rd US Rock Mechanics Symposium 

held in Asheville, 2008. ARMA, American Rock Mechanics 

Association 

Beck, D. A., Kassbohm, S and Putzar, G. Multi-scale 

simulation of ground support designs for extreme tunnel 

closure. In Caving 2010. Ed: Y Potvin. Australian Centre 

for Geomechanics, Perth, Australia. pp 451-454. 

Hodge, P.G. 1958. The mathematical theory of plasticity, 

In: Elasticity and plasticity, John Wiley and Sons, New 

York. 

Davis, E.H. 1968. Theories of plasticity and the failure of 

soil masses, In: Soil Mechanics: Selected Topics, 

Butterworths, London 

Lubliner, J. 1990. Plasticity Theory, Macmillan Publishing 

Company, New York. 

Drucker, D.C., Prager, W. and Greenberg, H.J. 1952. 

Extended limit design theorems for continuous media, 

Quart. Appl. Math., Vol9, 381-389 

Hill, R. 1951. On the state of stress in a plastic-rigid body 

at the yield point, Phil. Mag., Vol 42, 868-875. 

Villaescusa, E., M. Sandy and S. Bywater 1992. Ground 

support investigations and practices at Mount Isa: Proc. 

Int. Symp. on Rock Support. Sudbury Ontario Canada, 

pp 185-193, Balkema. 

Windsor, C.R. and A.G. Thompson 1993.Rock 

Reinforcement - Technology, Testing, Design and 

Evaluation.Comprehensive Rock Engineering (J A Hudson, 

ed.), Volume 4, Chapter 16, 451-484, Pergamon Press, 

Oxford. 

Hodge, P.G. 1958. The mathematical theory of plasticity, 

In: Elasticity and plasticity, John Wiley and Sons, New 

York. 

Davis, E.H. 1968. Theories of plasticity and the failure of 

soil masses, In: Soil Mechanics: Selected Topics, 

Butterworths, London 

Lubliner, J. 1990. Plasticity Theory, Macmillan Publishing 

Company, New York. 

Drucker, D.C., prager, W. And Greenberg, H.J. 1952. 

Extended limit design theorems for continuous media, 

Quart. Appl. Math., Vol9, 381-389 

Hill, R. 1951. On the state of stress in a plastic-rigid body 

at the yield point, Phil. Mag., Vol 42, 868-875. 



STUDY OF WELLBORE STRESSES AND STABILITY BASED 

ON A HOLLOW CYLINDER MODEL 

P.A. Nawrocki, Z. Qi and D. Wang 

Department of Petroleum Engineering, The Petroleum Institute, P.O. Box 2533, Abu Dhabi, UAE 

ABSTRACT 

The linear elastic theory has been used in the parametric analysis of borehole stresses in the hollow 

cylinder model. The analysis has been conducted in terms of two major parameters that introduce different 

geometries and loading conditions and have significant influence on the critical wellbore pressures. Different 

outer diameters and different hole sizes have been considered and their impact on stresses and failure 

investigated, both for dry and saturated rock. The Mohr-Coulomb, the Drucker-Prager and the Modified 

Lade criterion have been used and the safe mud weight window has been defined in each case. It has been 

shown that pore pressure plays an important role in borehole stability and that the Mohr-Coulomb criterion 

is a safe but apparently conservative choice as it predicts higher well collapse pressure than the other two 

criteria. On the other hand, the Drucker-Prager criterion is a very optimistic criterion that predicts very 

lowest values of collapse pressure, but it significantly overpredicts the σ 2 

strengthening effect. Providing 

predictions between the extremes of the other two criteria, the Modified Lade criterion is a moderate 

criterion that seems to account for the σ 2 

strengthening effect in a reasonable way and give reasonable 

mud weight choices required for maintaining well stable. 

SUBJECT : Stress analysis, wellbore stability, modelling, numercial methods 

KEYWORDS : Numerical modelling, rock stress, stability analysis, rock failure, rock properties. 

1. INTRODUCTION 

Hollow cylinder modeling is often used in wellbore stress 

and strain distribution estimation, borehole stability 

analysis and sand production prediction [1-4] . Hollow 

cylinders have the advantage that their configuration is 

similar to underground openings and that makes them an 

ideal tool to simulate wellbore situations. As for stress 

and strain distribution estimation and borehole stability 

analysis, a number of theories and approaches of hollow 

cylinder modeling have been proposed. Classic elastic 

theory [1] has been widely used to analyze the stress 

concentrations around open holes and borehole stability. 

It assumes the formations with isotropic properties and 

elastic behavior and can be used to provide approximation 

to the stress, strain and displacement distribution around 

underground openings. Elastic-plastic theory [4,5] has been 

proposed to analyze more complex rock behaviour and 

poroelastic theory [6,7] has been also used as it can account 

for the coupled interaction between rock matrix and 

saturating fluids. In addition, finite element simulations 

have been successfully conducted [8] to simulate the stress 

distributions and rock failure around wellbores under 

different loading conditions. 

The linear elastic theory has been used in this paper to 

conduct the analysis of stress, the displacement 

distribution and borehole stability. Firstly, different loading 

conditions have been applied to the hollow cylinder to 

analyze the influence of the internal and external pressure 

on the stress and displacement. Secondly, different outer 

diameters and hole sizes have been chosen to investigate 

their impact on stress and displacement distribution. 

Furthermore, three widely used failure criteria, the Mohr- 

Coulomb (considered the conventional “triaxial” criterion), 

the Drucker-Prager, and the Modified Lade criterion have 

been used to explore and compare the variation trends of 

critical wellbore pressures under the above two conditions. 

Both dry and saturated conditions have been considered 

and some practical recommendations for maintaining 

wellbore stability have been formulated. 

2. ROCK FAILURE CRITERIA 

Failure criteria provide limits to wellbore stresses and 

knowledge of rock strength is essential for accurate rock 

failure analysis and wellbore instability prediction. They 

are derived from laboratory tests on rock samples and 

can be typically divided into those that depend on all three 

principal stresses, σ 1 

, σ 2 

, and σ 3 

, and those that neglect 

the effect of the intermediate principal stress σ 2 

on failure. 

The Mohr-Coulomb criterion belongs to the latter group 

and is thus applicable to conventional triaxial test data 

(σ 1 

> σ 2 

= σ 3 

). The two “triaxial” criteria, i.e. the Modified 

Lade and the Drucker-Prager criterion, consider the 

influence of the intermediate principal stress in polyaxial 

strength tests (σ 1 

>σ 2 

>σ 3 

). They are compared to Mohr- 

Coulomb in Fig. 1. 


Study of Wellbore Stresses and Stability based on a Hollow Cylinder Model 

11 

...(6) 

Note that S o 

can be linked to C o 

and ϕ through S o 

= C o 

/2q 1/ 

2 

where q = [(μ 2 +1) 1/2 + μ] 2 = tan 2 (π/4 + ϕ/2]. 

Fig. 1 : Comparison of different rock failure criteria 

in the π-plane. 

Mohr proposed that when shear failure takes place across 

a plane, the normal stress σ n 

and the shear stress τ across 

that plane are related by 

|τ| = S o 

+ μs n 

...(1) 

where S o 

= cohesion and μ = the coefficient of internal 

friction of the material which is related to the angle of 

internal friction ϕ of that material by μ = tanϕ. Since the 

sign of τ only affects the sliding direction, only the 

magnitude of τ matters. Presented in terms of principal 

stresses, the Mohr-Coulomb criterion is: 

σ 1 

= C o 

+ σ 3 

tan 2 β ...(2) 

where σ 1 

= the major principal effective stress at failure, 

σ 3 

= the least principal effective stress at failure, C o 

= the 

uniaxial compressive strength, and β gives the orientation 

of the failure plane and is related to internal friction angle 

ϕ as β = π/4 + ϕ/2. In some formulations tan 2 β is replaced 

by q, where q = [(μ 2 +1) 1/2 + μ] 2 . 

The Lade criterion [9] is a three-dimensional failure criterion. 

Originally proposed for cohessionless sands, the criterion 

was then adopted for analyzing rocks with finite values of 

cohesion and tensile strength [10] and such a formulation 

was later linked [11] with standard rock mechanics 

parameters such as ϕ and S o 

to obtain: 

where I 1 

’ and I 3 

’ are stress invariants 

...(3) 

I 1 

’ = [(σ 1 

+ S – P p 

)+(σ 2 

+ S – P p 

) +(σ 3 

+ S – P p 

) ...(4) 

I 3 

’ = [(σ 1 

+ S – P p 

)(σ 2 

+ S – P p 

) (σ 3 

+ S – P p 

) ...(5) 

where S and η are material constants, and P p 

is the pore 

pressure. The parameter S is related to the cohesion of 

the rock, while η represents the internal friction. These 

parameters can be derived directly from the Mohr-Coulomb 

cohesion S o 

and internal friction angle ϕ by 

The typical behaviour of the Modified Lade criterion is 

shown in Figs 1 and 2. In principal stress space criterion [3] 

has the form of a convex, triangularly shaped cone. The 

parameter η determines the shape of the cross-section in 

the π-plane: increasing values of h correspond to the crosssectional 

shape changes from circular to triangular with 

smoothly rounded edges, Fig. 1. When plotted in σ 1 

- σ 2 

space, the criterion first predicts a strengthening effect 

with increasing intermediate principal stress s 2 

followed 

by a slight reduction in strength once s 2 

becomes ‘‘too 

high’’, Fig. 2. Thus, the Modified Lade criterion seems to 

provide a good alternative to the Mohr-Coulomb criterion. 

Fig. 2 : Behaviour of different failure criteria in σ 1 

-σ 2 

space 

for different values of confining stress σ 3 

. 

The extended von Mises yield criterion, or the Drucker- 

Prager criterion, was originally developed for soil 

mechanics. The yield surface of that criterion in principal 

stress space is a right circular cone equally inclined to 

the principal-stress axes, Fig. 1. The intersection of the 

p-plane with this surface is a circle and the Drucker-Prager 

yield function has the form: 

1/2 

J 2 

= k + α 1 

J 1 

...(7) 

where 

J 1 

= (σ 1 

+σ 2 

+σ 3 

)/3 ...(8) 

J 2 

= [(σ 1 

-σ 2 

)+(σ 2 

-σ 3 

) +(σ 1 

-σ 3 

) 2 ]/6 ...(9) 

The material parameters α 1 

and k can be determined from 

the slope and the intercept of the failure envelope plotted 

1/2 

in the J 1 

- J 2 

space: α 1 

is related to the internal friction of 

the material and k is related to its cohesion. In this way, 

the Drucker-Prager criterion can be compared to the Mohr- 

Coulomb criterion. 

The Drucker-Prager criterion can be further divided into an 

outer bound criterion (or Circumscribed Drucker-Prager) and 

an inner bound criterion (or Inscribed Drucker-Prager). These 



two versions of the criterion come from comparing it with 

the Mohr-Coulomb criterion and are shown in Fig. 1. The 

inner Drucker-Prager circle only touches the inside of the 

Mohr-Coulomb criterion and the outer Drucker-Prager circle 

coincides with the outer apices of the Mohr-Coulomb 

hexagon. Then the parameters α 1 

and k are given as [12] : 

...(10) 

...(11) 

The first set of equations is valid for inscribed and the 

second set for circumscribed criterion. 

As can be seen from the last equations, α 1 

only depends 

on ϕ, which means that it has an upper bound for both 

cases. When ϕ = 90 o , μ = ∞ and tan 90 o = ∞, so the value 

of a converges to 0.866 in the Inscribed Drucker-Prager 

case and to 1.732 in the Circumscribed Drucker-Prager 

case. Fig. 3 shows the behaviour of α 1 

with respect to m. 

The asymptotic values are represented by thick dashed 

lines. As α 1 

is obtained from the slope of the failure 

1/2 

envelope in J 1 

- J 1 

space, according to its value we are 

able to discern whether the Inscribed or the Circumscribed 

Drucker-Prager can be applied to the data. On the other 

hand, if the value of α 1 

for a specific rock is greater than 

the upper bound (asymptotic value), the values of C o 

and 

μ cannot be obtained, which means that the Drucker- 

Prager criteria cannot be compared to Mohr-Coulomb. If 

it is not necessary to find the values of C o 

and μ then the 

Drucker-Prager failure criterion can always be applied. 

Fig. 3 : Lower and upper bound for Drucker-Prager 

parameter α 1 

: α 1 

(vertical axis) as a function of 

μ (horizontal axis). 

In Fig. 2 the behaviour of both versions of Drucker-Prager 

criterion is shown in comparison with other failure criteria 

used in the analysis presented in this paper. C o 

= 64.1MPa 

and μ = 0.63 has been used and it can be seen in Fig. 2 

that for fixed values of σ 2 

and σ 3 

, the Inscribed Drucker- 

Prager predicts failure at lower stresses than the 

Circumscribed Drucker-Prager, which behaves significantly 

different than the other criteria. With increasing σ 2 

, the 

Modified Lade criterion first predicts strengthening followed 

by a slight reduction in strength once σ 2 

becomes ‘‘too 

high’’. Thus, the Modified Lade criterion seems to provide 

a good alternative to the Mohr-Coulomb criterion. Note 

that it was indicated before [12] that when trying to find the 

best criterion to fit the test data on different rocks, the 

Mohr-Coulomb triaxial failure criterion always yielded 

comparable misfits. Furthermore, the Modified Lade 

polyaxial criterion gave very similar fits of the data and 

the Drucker-Prager criterion did not accurately indicate 

the value of σ 1 

at failure and had the highest misfits. 

3. ANALYSIS 

The general hollow cylinder configuration with the inner 

radius R i 

and the outer radius R o 

is considered. The external 

pressure in the cylinder is P o 

, the internal pressure P i 

and 

the axial pressure is F. Utilizing linear elastic theory, the 

hollow cylinder stress equations can be written as [13] : 

...(12) 

...(13) 

...(14) 

If pore pressure is taken into account, the effective hollow 

cylinder stresses are given as the difference between the 

respective total stress, radial (σ r 

), hoop (σ θ 

) or axial (σ z 

), 

and the pore pressure term α B 

- P p 

, where α B 

is the Biot’s 

constant. 

The above linear elastic theory has been applied to perform 

wellbore stability analysis. The computation starts with 

converting the applied loads P i 

and P o 

into wellbore stresses 

σ r 

and σ θ 

. The wellbore stresses are then substituted into 

failure criteria to determine the critical wellbore pressure and 

identify the upper and lower bound mud weights. 

Subsequently, the “safe mud weight window” can be 

generated. When the internal pressure P i 

is small, the 

difference between the tangential and radial stress is 

significant and shear failure may occur. This critical internal 

pressure for shear failure corresponds to the lower bound 

coll 

mud weight and is called the “collapse pressure” P i 

. On 

the other hand, when the internal pressure P i 

increases to a 

high value, the tangential stress σ q 

will be negative and that 

indicates that the tangential stress turns to tensile state. 

Tension failure will occur when this stress surpasses the 

tensile strength of the wellbore rock. The corresponding 

internal pressure is the upper bound mud weight called the 

frac 

“fracturing pressure” P i 

. The difference between these two 

extreme pressure values is the “safe mud weight window”. 

Thus, low P i 

values favor shear failure; tensile failure at the 

wellbore wall can be expected for high well pressures. 



13 

The three failure criteria mentioned above, i.e., Mohr- 

Coulomb, Drucker-Prager and Modified Lade criterion, 

have been used in the analysis outlined above to predict 

the critical collapse pressure and tensile failure criterion 

has been used to predict the critical fracturing pressure. 

Then the results obtained from different failure criteria 

have been compared. Furthermore, the parametric 

analysis about the stress state and critical pressures has 

been conducted. Two ratios, the ratio of external and 

internal radius and the ratio of external and internal 

pressure, have been identified as crucial parameters that 

have significant influence on the critical internal pressure. 

To assess the influence of pore pressure on stability, the 

critical internal pressures have been estimated for two 

scenarios: with and without the pore pressure, and the 

big difference between these two cases has been 

observed. The set of rock strength and in situ stress 

data from one oilfield in the UAE has been used in 

calculations. It is shown in Table 1 where σ h 

is the in-situ 

horizontal stress, σ v 

is the vertical stress, and analysis 

has been performed in terms of two parameters α and β 

defined as 

R o 

= αR i 

and P i 

= βP o 

...(15) 

Table 1 : Rock properties and in situ stress data 

Depth σ h 

σ v 

P p 

S o 

β 

(m) (MPa/ (MPa/ (MPa/ (MPa) (degree) 

100m) 100m) 100m) 

2134 1.39 2.35 1.13 11.2 32.7 

3.1 Maximum Shear Stress 

The wellbore stresses σ r 

, σ θ 

and σ z 

were obtained by 

solving Eqs. 12-14. The three principal stresses σ 1 

, σ 2 

and σ 3 

were identified based on their magnitudes. Then, 

the maximum shear stress τ max 

was calculated as τ max 

= 

(σ 1 

-σ 3 

)/2. Fig. 4 shows the variation of τ max 

with the radius 

ratio α. As α increases, the maximum shear stress 

decreases, sharply at first and then remains approximately 

constant. Thus, the maximum shear stress τ max 

is very 

sensitive to wall thickness if the hollow cylinder is thin. 

Then a tiny increment in wall thickness can result in 

significant shear stress reduction. However, the maximum 

shear stress τ max 

is much less sensitive to wall thickness 

for the thick-walled cylinder. This can provide guidelines 

for scaling the laboratory hollow cylinder stress data into 

the real wellbore situation where α is infinite. 

Fig. 4 also shows the impact of β on τ max 

. As β decreases 

from 1.0 to 0, τ max 

will increase accordingly. In other words, 

the larger the difference between P i 

and P o 

is, the greater 

the τ max 

is. Therefore, if P o 

is fixed (such as in-situ horizontal 

stresses) and the internal well pressure continues 

decreasing (such as mud weight-related drilling pressure), 

τ max 

in the inner wall will continuously increase until shear 

failure will occur. 

Fig. 4 : Maximum shear stress at R i 

as function of α and β. 

3.2 Minimum Internal Well Pressure 

Figs. 5 and 6 show the influence of failure criteria, radius 

ratios and pore pressure on the lower bound mud weight, 

which is the minimum internal well pressure required to 

maintain wellbore stable. Firstly, the influence of failure 

criteria on minimum internal pressure becomes quite 

obvious through comparing the two sets of curves. The 

Mohr-Coulomb criterion is the most conservative criterion 

and the Drucker-Prager criterion is the most nonconservative 

one. The Mohr-Coulomb criterion predicts 

the highest critical β. That is mainly because the Mohr- 

Coulomb criterion is a two-dimensional criterion that only 

considers σ 1 

and σ 3 

. Therefore, the strengthening effect 

of the intermediate principal stress is ignored and borehole 

strength is underestimated. However, the Drucker-Prager 

criterion gives us the lowest critical β. That is mainly due 

to its overestimation of the intermediate principal stress 

strengthening effect. The Modified Lade criterion is a 

moderate one that is between the above two extreme 

criteria as it seems to properly account for the influence 

of σ 2 

on rock strength. These results are consistent with 

the results obtained by Zhang et al [14] . 

Fig. 5 : The effect of failure criterion on β-collapse 

including pore pressure effects 



Fig. 6 : The effect of failure criterion on β-collapse, dry case. 

The radius ratios a also plays an important role in 

determining the minimum internal pressure. As we know 

from Section 3.1, the maximum shear stress τ max 

will 

decrease when a increases. That means the inner hole 

can sustain much more pressure difference between 

internal and external pressures. Therefore, the minimum 

internal pressure β for preventing wellbore collapse could 

be reduced as the radius ratio α increases. Furthermore, 

when the radius ratio α goes up to a certain value, the 

minimum internal pressure β will not keep increasing but 

will remain approximately constant. This conclusion 

provides guidelines for scaling the lab hollow cylinder test 

data into the real wellbore situation where α is infinite. 

Pore pressure is another crucial parameter to affect the 

minimum internal pressure, which will be discussed in 

Section 3.4. 

3.3 Maximum Internal Well Pressure 

Fig. 7 shows us the influence of radius ratios and pore 

pressure on the upper bound mud weight, which is the 

required maximum internal pressure to maintain wellbore 

stable. As we know from Section 3.1, the maximum shear 

stress τ max 

will reduce if a increases. That means the 

inner hole can sustain much more pressure difference 

between internal and external pressures. Therefore, the 

maximum internal pressure β for preventing wellbore 

fracturing could be enhanced as the radius ratio α 

increases. 

In addition, the gap between the two curves indicates 

the effect of pore pressure P p 

on the maximum internal 

pressure β required for fracturing. As we can see, β- 

fracturing with pore pressure is obviously smaller than 

that without pore pressure. That is mainly because the 

pore pressure reduces the effective stresses and reduces 

the critical β-fracturing. Hence, if pore pressure is ignored 

when designing the mud weight on the oilfield, the inner 

wall stability will be overestimated and β-fracturing will 

be much greater than real condition. Then the inner wall 

will be at risk of developing mud leakage or the wall will 

break down. 

Fig. 7 : The effect of pore pressure on β-fracturing. 

3.4 Safe Mud Weight Window – Pore Pressure 

Effects 

Fig. 8 shows the safe mud weight window when pore 

pressure is taken into account and Fig. 9 shows the safe 

mud weight window when pore pressure is ignored. The 

comparisons of these two figures demonstrate the pore 

pressure effects on safe mud weight window. Take the 

Mohr Coulomb criterion for example. If the pore pressure 

is taken into consideration, the safe mud weight is between 

11.5 and 15.5 lb/gal. On the other hand, the safe mud 

weight will be approximately between 5 and 24 lb/gal if 

pore pressure is ignored. Also note that the mud weight 

window is much narrower if the pore pressure is taken 

into account. Pore pressure will weaken rock strength by 

reducing the confining pressure in the formation and thus 

will also reduce wellbore stability. 

Fig. 8 : The required mud weight with pore pressure 

The differences among the three failure criteria have been 

shown clearly through the analysis performed. The Mohr- 

Coulomb criterion is the apparently conservative one, the 

Drucker-Prager criterion is the non-conservative one, and, 

accounting for the intermediate principal stress 

strengthening effect in a reasonable way, the Modified 

Lade criterion is a moderate one. These results also 

confirm the impact of the hollow cylinder size on the critical 

mud weight. As the hollow cylinder thickness increases, 



15 

the mud weight window is getting wider, so it is easier to 

avoid instability problems. Note that the minimum and 

maximum mud weights change only slightly and stay 

approximately constant when α is greater than a certain 

value, such as 3 or 4. This phenomenon can be used to 

predict the wellbore stability problems by virtue of hollow 

cylinder testing. 

Fig. 9 : The required mud weight without pore pressure 

4. CONCLUSIONS 

A hollow cylinder model was used in this paper to conduct 

the parametric analysis of wellbore stresses and stability 

in terms of three major parameters that have significant 

influence on the critical internal wellbore pressure, such 

as radius ratio α, pressure ratio β, and pore pressure P p 

. 

Different values of these parameters give rise to different 

stress distributions in the hollow cylinder and, 

subsequently, affect the critical internal pressures. In 

addition, the critical internal pressure also depends on 

the failure criterion and three popular failure criteria such 

as Mohr-Coulomb, Drucker-Prager, and the Modified Lade 

criterion have been considered in this paper. Several 

conclusions can be drawn from this work. 

Firstly, the radius ratios a has great impact on the minimum 

and maximum critical internal pressure. As this ratio 

increases, the minimum internal pressure decreases and 

the maximum internal pressure increases. In other words, 

the safe mud weight window will be widened if the radius 

radio increases. In addition, the minimum and the maximum 

mud weights change only slightly and remain approximately 

constant when a is greater than a certain value. This 

phenomenon can be used to scale the lab hollow cylinder 

test data up to the scale of wellbore stability problems. It 

also means that, from stress point of view, it is easier to 

control stability of an oilfield well than of a small hollow 

cylinder sample tested in laboratory environment. 

Secondly, pore pressure also plays an important role in 

borehole stability analysis and mud weight design. It can 

significantly weaken the rock by reducing confining stress, 

thus narrowing down the safe mud weight window to a 

great degree. When pore pressure effects and effective 

stresses are considered, the safe mud weight window is 

much narrower than when compared to the dry rock case. 

Hence, neglecting pore pressure (or inaccurate pore 

pressure estimation) will have misleading effect on safe 

mud weight choices and may result in triggering wellbore 

instability problems. 

Finally, this analysis confirms the differences and 

characteristics of the three yield criteria considered in this 

paper. The Mohr-Coulomb criterion is apparently 

conservative. It is a two-dimensional failure criterion that 

does not account for the intermediate principal stress 

strengthening effect. The Drucker-Prager criterion is 

apparently non-conservative and over predicts the s 2 

strengthening effect. The Modified Lade criterion is a 

moderate one, between the extremes of the other two criteria. 

Thus, it can provide reasonable mud weight predictions. 

Acknowlegdements : Support from the Petroleum 

Institute and local operating companies for the work 

covered in this paper is gratefully acknowledged. 

REFERENCES 

1. Jaeger J., Cook, N.G.W., and Zimmerman R. 2007, Fundamentals 

of rock mechanics, 4th edition, Blackwell Publishing. 

2. Santarelli F.J. and Brown E.T. 1989, Failure of three sedimentary 

rocks in triaxial and hollow cylinder compression tests. Int. J. 

Rock Mech. Min. Sci. Geomech. Abstr. 26 (5): 401-13. 

3. Chen X., Tan, C.P., and Haberfield C.M. 2000, Numerical 

evaluation of the deformation behaviour of thick-walled hollow 

cylinders of shale. Int. J. Rock Mech. Min. Sci. 37 (6): 947-961. 

4. Wang Y. and Wu B. 2001, Borehole collapse and sand production 

evaluation: experimental testing, analytical solutions and field 

implications. Proc. 38 th U.S. Symp. on Rock Mech., DC Rocks 

2001: Rock Mechanics in the National Interest, Washington DC, 

July 7-10, Elsworth, Tinucci and Heasley (eds). 

5. Marsden J.R., Dennis, J.W. and Wu B. 1996. Deformation and 

failure of thick-walled hollow cylinder of mudrock, a study of 

wellbore instability in weak rock. Proc. Eurock’96, Barla (ed). 

6. Biot M. A. 1941. General theory of three-dimensional consolidation. 

J. Appl. Phys. 12: 155-164. 

7. Kanj M. and Abousleiman Y. 2005. Fully-Coupled 

porothermoelastic analysis of anisotropic hollow cylinders with 

applications. Int. J. Num. Anal. Meth. Geom. 29 (2): 103-126. 

8. Zhou X. and Ghassemi A. 2009, Finite element analysis of coupled 

chemo-poro-thermo-mechanical effects around a wellbore in 

swelling shale. Int. J. Rock Mech. Min. Sci., 46 (4): 769-778. 

9. Lade P.V. and Duncan J.M. 1975. Elastoplastic stress-strain 

theory for soil. J. Geot. Eng. Div. ASCE, 101: 1037. 

10. Lade P.V. 1984. Failure criterion for frictional materials, Mechanics 

of Engineering Materials, Ch. 20, Desai and Gallagher (eds.), 

Wiley, 385-402. 

11. Ewy R.T. 1998. Wellbore stability predictions using a modified 

Lade criterion, Eurock 98, Trondheim. 

12. Colmenares L. B. and Zoback M. D. 2002. A statistical evaluation 

of intact rock failure criteria constrained by polyaxial test data for 

five different rocks, Int. J. Rock Mech. & Min. Sci., 39: 695-729. 

13. Hoskins E.R. 1969. The failure of thick-walled hollow cylinders of 

isotropic rock. Int. J. Rock Mech. & Min. Sci. 6: 99-125. 

14. Zhang L., Cao, P. and Radha K.C. 2010. Evaluation of rock 

strength criteria for wellbore stability analysis. Int. J. Rock Mech. 

Min. Sci. 47: 1304-1316. 



ENGINEERING GEOLOGICAL AND GEOTECHNICAL 

EVALUATION OF DAM SPILLWAY (II-C) OF BUNAKHA 

HYDROELECTRIC PROJECT, BHUTAN HIMALAYA 

A.K. Naithani, L.G. Singh and Devendra Singh Rawat 

National Institute of Rock Mechanics, Kolar Gold Fields, Karnataka 

P.C. Nawani 

Former Director, NIRM, H.No. 273, Nirvana Country, Sector 49-50, Gurgaon, Haryana 

ABSTRACT 

The 193.3 m long and 64 m wide spillway of Bunakha Hydroelectric Project is proposed 89.50 m from the 

right abutment to pass the flood discharge and lies mainly on the right abutment and partly in the river 

section. The spillway area was investigated through detailed engineering geological mapping, exploratory 

drilling and laboratory testing. The rock mass properties, i.e., joint sets, weathering grade, RQD, RMR, 

permeability etc. of the rock masses to be encountered during the excavation of spillway have been 

analyzed in detail. Core samples from the exploratory drill holes drilled at the spillway alignment were 

tested for physico-mechanical properties of rocks in the laboratory. The mapping details indicated that the 

major rock types which are exposed to the surface and cover the entire spillway area are foliated gneisses 

with bands of banded gneisses. On the basis of detailed investigations and laboratory testing, inferences 

and recommendations have been made which will be helpful during the construction of the project. 

Keywords: Hydroelectric, Rock Mass Rating, Spillway, Thimphu Formation, Bhutan 

INTRODUCTION 

The proposed Bunakha Hydroelectric Project (BHEP) for 

generation of 180 MW (3 x 60 MW) hydropower is located 

near village Bunakha, in Chukha Dzong (District) in the 

Western Bhutan, covering toposheet No. 78E/11 & 78E/ 

12 India and adjacent country series. BHEP is the upper 

most major project in the development of the power 

potential of the Wang Chhu river in Bhutan. Wang Chhu is 

formed by the confluence of two major snow-fed rivers 

viz. Paro Chhu and Thimphu Chhu, join at an elevation of 

2068 m at Chhuzom, i.e., upstream from the proposed 

project site. BHEP is a storage project utilizing the head 

upstream of the existing Chukha HE Project (336 MW) 

and the confluence of Paro Chhu and Thimphu Chhu. This 

proposed storage scheme envisages important structures 

such as 198 m high concrete dam, spillway, intake, steel 

lined pressure shafts partly along the slope of the nonoverflow 

section and partly through the underground 

excavation, power house and a tail race channel. The 

estimated gross storage of this project is about 237.52 

MCM. In the spillway area, river Wang Chhu flows in 170 o 

direction and takes a south-westerly turn after the 

confluence with Sherjalum Chhu. The confluence of 

Sherjalum Chhu with Wang Chhu is at an elevation of 

1848 m. In this paper attempt has been made to bring out 

the rock mass condition of the foundation of the spillway 

of new dam axis (II-C) on the basis of detailed engineering 

geological mapping, geological logging of drill holes, rock 

mass permeability values, and laboratory test result. The 

basic purpose of these investigations was to identify / 

map different rocks and structures like joints, shear zones, 

faults, fracture zones etc and to determine engineering 

properties of rock by lab testing. Rock mass classification 

using Rock Mass Rating (RMR) system [Bieniawski, 1979, 

1989] was attempted. The rock mass classification can 

be used for estimating the unsupported span, the standup 

time and the support pressures of an underground 

opening. It can be also be used for selecting a method of 

excavation and permanent support system. 

The spillway is proposed 89.50 m from the right abutment 

of the dam to pass the flood discharge and lies mainly on 

the right abutment and partly in the river section. The 

length of spillway is 193.30 m (up to Flip Bucket) and the 

overall width of the spillway is 64.00m. The crest of the 

spillway is at EL 1917.50 m. The flood/MPF through the 

spillway will be regulated by means of six gates each of 

size 6.0 m (width) x 9.0 m (height). The waterway for the 

spillway has been designed to cater to the Maximum 

Probable Flood (MPF) with a peak discharge of 10028 

Cumecs and the total flood volume of about 845 million 


Engineering Geological & Geotechnical Evaluation of Dam Spillway (II-C) of Bunakha Hydroelectric Project, Bhutan 

17 

cubic meters. The FRL of 2006 m has been finalized by 

regulating the PMF of 10028 Cumecs through the low level 

sluice spillway. The chosen FRL of 2006 m has the 

advantage of avoiding the submergence of the 

Phuentsholing-Thimphu national highway and restricting 

the submergence of agricultural land and consequent socioeconomic 

impacts. 

GEOLOGY OF THE PROJECT AREA AND AROUND 

The bedrock encountered at the proposed project site at 

Bunakha is represented largely by crystalline rocks of 

Thimphu Gneissic Complex belonging to upper amphibolite 

facies of metamorphism [Jangpangi, 1978; Gansser, 

1983]. Earlier, geologically, the project area was 

investigated by Chowdhury [1993, 1995] and Mishra and 

Sanwal [1994]. The litho-units of Thimphu Gneissic 

Complex at site are characterized by heterogeneous 

lithology consisting of foliated gneisses, streaky and 

banded gneisses, amphibolite gneisses with large boudins 

and bands of quartzite and thin interlayer of mica schists/ 

foliated gneisses with large porphyroblasts of garnet 

measuring up to 4 mm and bands of calc-silicate gneisses. 

Quartz porphyroblasts are stretched and boudinaged and 

show undulose extinction. On the surface of spillway area 

garnetiferous foliated gneisses and banded gneisses have 

been mapped while drilling confirmed a sequence of 

foliated gneisses, banded gneisses, amphibolite gneisses 

and calc-silicate gneisses at different depths. 1.6 km 

upstream from the spillway, there is a thrusted contact 

(MCT-I) between the rocks of Thimphu and Paro 

Formations. In general, formations (bedding/foliation S-1) 

show low to moderate (10 o to 35 o ) dip excepting in areas 

adjoining to faults/ fractures where local steep dips are 

noted. Overturned and recumbent folds in the rocks of 

Thimphu Formation has been reported by most of the 

earlier worker [Nautiyal et.al. 1964; Guha Sarkar, 1979; 

Ray et.al. 1989; Bhargava and Dasgupta, 1995, Bharhava, 

1995; Koike, 2002]. The rocks of Thimphu Formation at 

spillway dam site are folded into N-S trending antiform 

with low angle (20 o -30 o ) southerly plunge (4500 > 80 

2 Foliated Gneisses (FG) Grade – II 3500 – 4500 60 – 80 

3 Alternate Band of Gneisses Grade – III 3000 – 3500 40 – 60 

with Calc-silicate (ABG) 

4 Schistose Quartzite (SQ) Grade – II 3500 – 4500 60 – 80 

5 Shear Zone (SZ) Grade – IV 2000 – 2500 < 1 

6 Weathered Rocks (WR) (II-IV) Grade Changes 1500 – 2500 < 10 

7 Destressed Rock (DR) - 2500 – 3000 30 – 40 



GEOTECHNICAL INVESTIGATIONS 

Geological Mapping 

Understanding the geological and structural setup of an 

area constitutes one of the important parameters required 

for economic and safe designing of a civil structure. For 

the design of spillway structure detailed examination of 

the lithological units and geological structures (e.g., faults, 

joints, shear zones, folds etc.) and nature of the river 

valley are particularly important. Moreover, foundation 

conditions and type of construction to suit the foundation 

structure are very important for techno-economic design 

of engineering structure. Therefore, in order to forecast 

the geology along the spillway alignment and to estimate 

the rock mass characteristics, detailed engineering 

geological mapping has been carried out on 1:1000 scales 

with 2 m contour intervals by deploying Total Station. The 

map prepared during detailed investigation depicts the 

boundaries of different geological units with structural data, 

areas covered by overburden, boulders, river and streams 

at the spillway site (Fig. 1). 

In the spillway area on the surface foliated gneisses 

interlayer with banded gneisses which are generally 22 o 

to 30 o in disposition for considerable distance both on the 

up-stream and down-stream sides are present. From dam 

axis up to 200 m on the surface on right bank foliated 

gneisses are exposed for which joint volume (Jv) 24 was 

recorded. Presence of medium grained greyish white 

foliated gneisses, banded gneisses with bands of calcsilicate 

gneisses and amphibolite gneisses are confirmed 

from Drill holes data. The site for junction point of spillway 

Fig. 1 : Geological plan map of dam spillway (II-C) 

with stilling basin has been finalized in such a way that it 

should not be affected by the discharge from the Shirjalum 

Chhu, which is charged with boulders gushing down at 

high velocity during cloudburst would endanger the stilling 

basin. The stilling basin is kept on right bank, i.e., away 

from Shirjalum Chhu but diversion of the Shirjalum Chhu 

and construction of boulder traps in the upper reaches 

shall have to be considered. 

The geological mapping at the project site confirm that 

the river Wang Chhu flows along the N-S trending axial 



19 

zone of the antiform with low angle (


conducted in spillway drill holes, at increasing and 

decreasing cycle of pressure, to determine rock mass 

permeability values. Core samples from the boreholes 

were tested for physico-mechanical properties of rocks in 

the laboratory. 

Table 2 : Prominent joint sets developed in gneisses at dam spillway site 

Type of Strike or Spacing Persistence Roughness Aperture Infilling Ground Remarks 

Joint/ Joint Dip (cm) (m) (mm) Water 

Set 

Direction/ 

Dip 

Foliation J1 N200 o /25 o 12-60 >20 m Smooth Tight to 10 Sheared Dry Shear zones are 

undulating gaugy some times formed 

material 

along this joint, 

foliation dipping 

toward downstream 

side (22°- 

30°). 

Inclined J2 N055 o /55 o 40-60 1 – 5 Rough 12 None Dry Joint dipping 

undulating toward valley, 

often controls the 

valley slope. 

Subvertical N095 o /80 o Random >20 Smooth planar 4 None Dry Valley dipping joint, 

J3 

perpendicular to 

dam axis, often 

control the valley 

slope. 

Vertical J4 N055 o -070 o /V >18 >20 Smooth planar 3-5 None Dry Vertical Joint, 

oblique to dam axis 

Table 3 : Description of drilling data from spillway alignment area 

Drill Location Total Angle with Reduced Overburden Weathering Drill Core RQD Brief 

Hole Depth Horizontal Level of (m) Grade Water Recovery (%) Description 

No (m) Ground Loss (%) of Rock 

(m) 

Types 

DH-03 71.47m d/s 75.0 90 1849.29 13.50 W-I - W-III Partial – 0-80 0-35 Banded gneiss 

of dam axis Collar Complete with schistose 

II-C, centre Elevation parting 

of river 

DH-06 162.50m d/s 50.30 90 1849.21 5.0 W-I - W-III Partial 0-100 0-58 Banded gneiss 

from dam axis Collar with schistose 

(II-C), river Elevation intercalations 

bed 

DH-13 47.00m d/s 150 90 1930.79 0.5 W-I - W-III Partial - 3.3-100 Nil-78.66 Foliated gneiss, 

perpendicular Complete banded gneiss, 

to dam axis calc silicate 

gneiss, amphibolite 

gneiss 

DH-14 15.50m d/s 126.0 59 1850.75 1.5 W-I - W-IV Partial - 8-94.7 Nil-74 Foliated gneiss, 

from dam Complete banded gneiss, 

axis (II-C), 

amphibolite 

right bank gneiss, calc 

silicate gneiss 

and schistose 

quartzite 

The cores recovered from these bore holes have been 

examined and logged geologically. Overburden in the river 

bed varies from 5.0 m to 13.50 m and bedrock occurs at 

level varying from RL 1832 m to RL 1844 m. Erratic 

weathering is indicated and level of moderately fresh rock 

(W-II) varies from RL 1827 m to 1836 m as reported from 

the drill hole DH-14. Excepting in the limited section of 

DH-14 drill core recovery is poor and retrieved core are 

fragmentary such that average RQD values are extremely 

poor (


21 

of schistose interlayers and foliation parallel shear zones 

(37 Lu. This has 

been ascribed to presence of close set of schistose 

interlayers and foliation parallel minor shear zones (


CONCLUSIONS 

Based on above studies, the following inferences and 

recommendations have been made: 

(a) The grade of the rock mass as evaluated from the drill 

holes cores, core recoveries and RQD, has RMR 

values varying from 35 to 55 and fall under the fair to 

poor rock category. 

(b) Along the spillway alignment, the rocks are dipping 

(low) in the downstream direction associated with low 

angle (

23 


GOVERNING COUNCIL FOR THE TERM 2011-2014 

President 

• Dr. H.R. Sharma, Chief Technical Principal-Hydro, Tractebal Engineering Pvt. Ltd. 

Vice President 

• Dr. R.K. Goel, Chief Scientist, Central Institute of Mining and Fuel Research, Regional Centre, Roorkee 

Immediate Past President 

• Dr. K.G. Sharma, Professor, Department of Civil Engineering, IIT Delhi 

Members 

• Dr. A.K. Dhawan, Chief Consultant, Fugro Geotech Pvt. Ltd. 

• Mr. R. Jeyaseelan, Former Chairman, Central Water Commission 

• Mr. Pawan Kumar Kohli, General Manager (Civil Design), H.P. Power Corporation Limited 

• Mr. D.M. Kudtarkar, Chief Technology Officer, Hindustan Construction Company Ltd. 

• Mr. P.K. Mahajan, VSM, Chief Engineer, Directorate General Border Roads 

• Mr. Ganesh Manekar, Chief (Mines), MOIL Limited 

• Mr. R.N. Misra, Director (Civil), SJVN Limited 

• Dr. A. Nanda, Deputy General Manager, Engineers India Limited, Sub Surface Projects Division 

• Mr. A.B. Pandya, Member (D&R), Central Water Commission 

• Dr. Rajbal Singh, Joint Director (Rock Mechanics), Central Soil and Materials Research Station 

• Dr. P.K. Rajmery, General Manager (Rock Mech.), Hindustan Zinc Ltd. 

• Dr. T. Ramamurthy, Visiting Professor, Department of Civil Engineering, Indian Institute of Technology Delhi 

• Dr. S. Sengupta, Scientist – V & HOD (Geotechnical Engineering Department) and Scientist-in-Charge - 

Bangalore Unit, National Institute of Rock Mechanics 

• Mr. D.K. Sharma, Head Project Development Hydropower, L&T Power Development Limited 

• Mr. M.S. Soin, Regional Executive Director (Hydro), NTPC Limited 

• Dr. Manoj Verman, Technical Director, Geodata India Pvt. Ltd. 

• Mr. R.K. Vishnoi, Assistant General Manager (DE&S –Civil), THDC India Ltd. 


• Mr. V.K. Kanjlia, Secretary, Central Board of Irrigation & Power 

Treasurer 

• Mr. A.C. Gupta, Director (WR), Central Board of Irrigation & Power 




SEMINAR ON 

“GEOTECHNICAL CHALLENGES IN 

WATER RESOURCES PROJECTS” 

19-20 January 2012, Dehradun (Uttarakhand) 

Inauguration of the Seminar (L-R) Mr. B.C.K. Mishra, Dr. R.K. 

Goel, Mr. M.M. Madan, Dr. K.G. Sharma and Mr. A.C. Gupta 

A view of the dais during the Inaugural Session 

Execution of multipurpose water resources projects located in complicated geological settings is a challenge to 

engineers. Despite tremendous all round advancement in technologies, there is still scope to learn and know more 

about the geotechnical challenges faced during excavations and its implications on design as well as execution. Both 

design and construction engineers would always be keen to know what advancements are taking place in their 

respective fields to face such challenges and utilize the knowledge for most economical and safe design for construction 

of a project. 

These projects require application of modern principles of rock mechanics, which warrants deliberations and collaboration 

to facilitate flow of appropriate technology to enable successful implementation of such projects under a time-bound 

programme in a cost-effective manner, conforming to environmental requirements. 

Safety during tunnel and underground construction is of paramount importance not only to the stability of structures 

but also to ensure safety of the work force. Safety in tunnels and cavities may be endangered due to sudden rock 

falls, geological failures, collapse of underground opening or a part of opening, etc. 

Considering the above, the Central Board of Irrigation & Power (CBIP) and the Indian National Group of International 

Society for Rock Mechanics (ISRM), organised a Seminar on “Geotechnical Challenges in Water Resources Projects” 

at Hotel Aketa, Dehradun on 19 and 20 January 2012. 

The objective of the proposed Seminar was to provide a forum for the design and construction engineers to discuss 

the solutions to various geological and geotechnical surprises encountered during the execution of various River 

Valley Projects and use the knowledge for safe and economical design and construction of such projects. 

The Seminar was co-sponsored by UJVN Limited. 

62 participants from 26 organisations, including from Bhutan, participated in the Seminar. 

The Seminar was inaugurated by Mr. B.C.K. Mishra, Director (Operations), UJVN Limited, on 19 th January 2012. The 

Inaugural Session was presided over by Mr. M.M. Madan, Director (Hydel), GVK Group. 

Papers/case studies on the following topics were presented and discussed during the Seminar: 



25 

• Latest Trends and Methods of Assessing Complex Foundation Conditions 

• Slope Stability Problems 

• Tunneling in Uncertain Rock Conditions and Fractured & Crushed Zones 

• Geotechnical Risk Evaluation and Rehabilitation of Existing Dams 

• Instrumentation and Monitoring Systems 

• Jet Grouting and Plastic Concrete Diaphragm Walls Techniques for Seepage Cut-Off 

• Use of Remote Sensing and GIS applications in Geotechnical Investigations and Interpretation 

• Geotechnical Aspects of Natural Disasters 

The Seminar concluded with the discussions on 20 th January 2012 under the Chairmanship of Mr. Manoj Basu, 

General Manager (Geotech), NHPC Limited. Mr. P.K. Kohli, General Manager (Designs), Himachal Pradesh Power 

Corporation Limited also participated in the discussions as panelist. During the session, participants discussed the 

problems being faced in the professional engagements and provided their feedback about the Seminar. 

INTERNATIONAL SEMINAR ON 

“SURVEY AND INVESTIGATIONS OF HYDROELECTRIC 

PROJECTS – ISSUES AND CHALLENGES” 

28 th March 2012, New Delhi 

A view of dais during the Inaugural Session (L to R) – Mr. S.P. 

Kakran, Mr. A.S. Bakshi, Mr. P. Uma Shankar, Mr. A.B.L. 

Srivastava and Mr. G. Sai Prasad 

Mr. P. Uma Shankar, Inaugurating the Exhibition 

The slippages in capacity addition for power sector, in general, and hydro, in particular, have been a matter of great 

concern. Environmental concerns, land acquisition, social issues, contractual issues and geological uncertainties 

are listed as major causes amongst the reasons cited for the delays. To overcome the problem of geologic uncertainties, 

the role of Survey & Investigation amongst many other factors cannot be under estimated. Accordingly, to study and 

analyze the situation and also gain first hand information about the international practices followed in this regard, an 

International Seminar on “Survey and Investigations of Hydroelectric Power Projects- Issues and Challenges” was 

organized by NHPC Limited in association with CBIP, the Secretariat of Indian National Group of ISRM, on March 28 th 

at CBIP Conference Hall, New Delhi. 

The Seminar was inaugurated by the Hon’ble Chief Guest, Secretary to Government of India, Ministry of Power, Mr. 

P. Uma Shankar, by lighting a ceremonial lamp along with Mr. G. Sai Prasad, Joint Secretary (Hydro), Ministry of 

Power, Mr. A.S. Bakshi, Chairperson, Central Electricity Authority, Mr. S.P. Kakran, Member, Central Water 



Commission and Mr. A.B.L. Srivastava, Chairman and 

Managing Director, NHPC Limited. 

There was participation of 112 senior representatives from 

Government Departments, Public Sector Utilities and the 

Private Sector. The seminar also attracted a large 

representation and presentations from International 

community with delegates from U.K., China, Switzerland 

and Italy. 

On the sidelines of the Seminar, an exhibition to showcase 

investigation capabilities of NHPC was organized as well. 

The exhibition was also inaugurated by Secretary, Ministry 

of Power, Government of India. Dr. Gopal Dhawan, 

Executive Director, briefed him about the latest equipment 

being used for Survey and Investigations and the 

techniques involved. The exhibition was visited by a 

number of participants and was greatly appreciated. 

The technical discussion took place in the following two 

sessions: 

• Identification of Challenges of Investigations of 

Hydroelectric Projects 

• Application of Techniques and Methods of 

Investigations of Hydroelectric Projects and Handling 

of Surprises. 

The Seminar Concluded with Panel Discussions on 

“Review of Current Survey & Investigation Practices and 

Way Forward”, and the Chairmanship of Mr. Brijendra 

Sharma, Advisor, Lanco Group and Former Executive 

Director, NHPC Limited. Mr. Matin C. Knights, Global 

A view of the delegates during the Seminar 

Leader, Halcrow and Former President, ITA, Prof. Xia- 

Ting Feng, Director, State Key Labs of Geomechanics & 

Geotech. Engg., China and President, ISRM and Dr. Y.P. 

Sharda, Sr. Specialist (Engg. Geology) at SNC-Lavalin, 

India and Former Director, GSI, deliberated on various 

issues during the panel discussions, as panelists. 

Finally the recommendations as framed by a committee 

of senior executives were read out by the Chairman and 

after discussion and modifications the same were approved 

by the house. 

The Seminar ended with a Vote of Thanks by Dr. Gopal 

Dhawan, Executive Director (Geotech/PID), NHPC Ltd. 

SEMINAR 

ISSUES IN APPRAISAL OF DETAILED PROJECT REPORTS 

OF HYDROELECTRIC PROJECTS 

22 June 2012, New Delhi 

A view of the dignitaries on dais during the Inaugural session (L to 

R): Mr. Alok Gupta, Member Hydro, CEA; Mr. R.C. Jha, Chairman, 

CWC; Mr. Devendra Chaudhry, Additional Secretary to Government 

of India, Ministry of Power; Mr. R.P. Singh, CMD, SJVN Limited and 

Mr. V.K. Kanjlia, Secretary, CBIP 

Framing a bankable DPR and getting it appraised in time 

is of utmost importance as this becomes as important 

document for power purchase agreement, borrowing loans 

from financial institutions or Banks, land acquisition, 

tender processing, preparation of detailed construction 

drawings and for the actual execution of the project. A 

well prepared DPR may avoid many uncertainties and also 

can reduce construction time of project. In order to achieve 

all these objectives, the expeditious approval of DPR also 

assumes importance. 

In this context, SJVN Limited (SJVNL) organised a 

Seminar on “Issues in Appraisal of Detailed Project Reports 

of Hydroelectric Projects”, in association with Central 

Board of Irrigation and Power (CBIP), the Secretariat of 

Indian National Group of ISRM, on 22nd June 2012 at 

CBIP Conference Hall, New Delhi. 



27 

Welcome address being delivered by Mr. R.P. Singh 

The purpose of the proposed seminar was to discuss the 

various issues involved in preparation of DPR & its 

approval process. Guidelines for formulation of detailed 

project report, norms for submission, acceptance, 

examination & concurrence by relevant authorities were 

discussed in the seminar. During proposed seminar, 

possible ways to minimize the time period involved in 

appraisal of DPRs were also discussed. 

There was participation of 136 representatives from 

Government Departments, Public Sector Utilities and the 

Private Sector. 

Following were the topics selected for discussions during 

the Seminar: 

• Guidelines for Formulation and Processing of DPRs 

for obtaining TEC/TEA. 

• Expectation of Appraising Authorities for Preparation 

of Quality DPRs. 

• General Deficiencies Observed in DPRs and 

Suggestion to Overcome Them 

• Difficulties Faced and Ways/Means for Obtaining 

Speedy Clearance of DPRs 

In total 08 presentations were made on the topics selected 

for discussions by the representatives of Central Electricity 

Authority, Central Water Commission, Geological Survey 

of India, Central Soil and Materials Research Station, 

SJVNL, North Eastern Electric Power Corporation Limited, 

Himachal Pradesh Power Corporation Limited and GMR 

Group. 

In addition, during the Inaugural Session of the Seminar, 

following ten journals, pertaining to Indian Chapter/Groups 

of 10 international organisations, whose Secretariats are 

in CBIP, were released by the dignitaries on dais: 

• Indian Journal of Geosynthetics and Ground 

Improvement 

Release of Journals by Mr. R.C. Jha 

Release of Directory of Key Personnel in Power, Renewable Energy 

and Water Resources Sectors - 2012 by Mr. Devendra Chaudhry 

• INCOLD Journal 

• ISRM (India) Journal 

• IWRA (India) Journal 

• NDC-WWC Journal 

• TAI Journal 

• IASH Journal 

• AARO Journal 

• Power Engineer Journal 

• CIGRE India Journal 

The Directory of Key Personnel in Power, Renewable 

Energy and Water Resources Sectors-2012, brought out 

by CBIP, was also released by Shri Devendra Chaudhry, 

Additional Secretary to Government of India, Ministry of 

Power, during the Inaugural Session. 

The Seminar ended with a Vote of Thanks by Mr. V.K. 

Kanjlia, Secretary, CBIP. 



ISRM NEWS 

ISRM COMMISSIONS AND JOINT TECHNICAL 

COMMITTEES 

The ISRM Board has appointed several Commissions for 

the period 2011-2015 in order that they may study some 

scientific and technical matters of topical interest to the 

Society. 

The current list of ISRM Commissions is : 

• Commission on Application of Geophysics to Rock 

Engineering 

• Commission on Coupled THMC processes in 

Geological Materials and Systems 

• Commission on Crustal Stress and Earthquake 

• Commission on Design Methodology 

• Commission on Discontinuous Deformation Analysis 

- DDA 

• Commission on Education 

• Commission on Hard Rock Excavation 

• Commission on Petroleum Geomechanics 

• Commission on Preservation of Ancient Sites 

The President of ISRM and the Presidents of the two 

Sister Societies, IAEG and ISSMGE created a number of 

Joint Technical Committees and approved the JTC 

Guidelines. These JTCs operate now under the umbrella 

of the Federation of International Geo-engineering 

Societies - FedIGS. 

The current list of JTCs includes : 

• JTC 1 - Joint Technical Committee on Landslides and 

Engineered Slopes 

• JTC 2 - Representation of Geo-engineering Data in 

Electronic Form 

• JTC 3 - Education and Training 

The ISRM and the International Tunnelling and Underground 

Space Association - ITA are cooperating in such a way 

that ISRM may appoint members to selected ITA Working 

Groups and ITA may appoint members to selected ISRM 

Commissions. Besides, a Joint Working Group / 

Commission on “Site Investigation Strategies for Rock 

Tunnels” is being set up, under the joint chairmanship of 

Conrad Felice from ITA and Rolf Christiansson from ISRM. 

NOMINATION FROM INDIA FOR ISRM COMMISSION 

ON EDUCATION 

ISRM Commission on “Education” is one of the 

commissions on various subjects. The purpose of the 

Commission is to organize activities and enhance teaching 

and training level of education on rock mechanics. 

Prof. Meifeng Cai, College of Resources Engineering, 

University of Science & Technology Beijing, is the 

President of the Commission. The other members of the 

commission are: 

• M.A. Kwasniewski (Poland) 

• N.F. Grossmann (Portugal) 

• M.U. Ozbay (USA) 

• J.P. Harrison (Canada) 

• J.A. Wang (China) 

• F. Pellet (France) 

• L. Jing (Sweden) 

• J. Zhao (Switzerland) 

• Xia-Ting Feng (ex-officio), ISRM President 

• Yingxin Zhou (ex-officio) ISRM Vice President (Asia) 

ISRM requested the Indian National Group to nominate a 

key person who is working at Indian University to be a 

member of ISRM Commission on Education. 

Prof. K.G. Sharma, Department of Civil Engineering, IIT 

Delhi, has been nominated as member of the Commission 

from India considering his exposure to teaching of rock 

mechanics, both at Undergraduate and Postgraduate levels. 

ISRM COUNCIL MEETING 

The International Society for Rock Mechanics held its 

Council meeting in Stockholm, Sweden, on 27 May 2012, 

in conjunction with EUROCK 2012, organised by the 

Swedish ISRM National Group and the Rock Engineering 

Research Foundation - BeFo. 41 of the 49 National Groups 

were either present or represented. The Council was also 

attended by two Past Presidents, the Chairmen of the 

ISRM Commissions, and representatives of the IAEG and 

the ICOLD. 

MEMBERSHIP OF THE ISRM 

The ISRM has now 6,783 individual members (an all-time 

record) and 140 corporate members, belonging to 49 

National Groups. This represents an increase of 4% in 

the number of individual members since the last year. 

46% of the members come from Europe, while Asia has 

been the fastest growing region in the last years. 

MODERNISATION OF THE ISRM 

The President, Prof. Xia-Ting Feng, during ISRM Council 

Meeting on 27 May 2012 in Stockholm, explained the 

modernisation initiatives that are underway. In particular, 

he focused on the Young Members Presidential Group 

which has recently been formed with members appointed 

by the NGs up to 35 years of age, on the steps being 

given towards the creation of the ISRM Foundation for 


ISRM News 

29 

Education and on the creation of an ISRM book series 

where books produced by the Commissions can be 

published. He also mentioned the efforts being made to 

increase the membership. 

THE ISRM 50TH ANNIVERSARY COMMEMORATIVE 

BOOK 1962-2012 LAUNCHED 

The ISRM was founded in Salburg in 1962 and is now 

commemorating its 50 th anniversary. The celebrations 

started in October 2011 during the 12th Congress in Beijing 

and continue during one year until they are closed in 

Salzburg at the 61 st Geomechanics Colloquy. 

At the 2012 International Symposium, in Stockholm, in 

May, a Commemorative Book was launched and an 

Historical Exhibition was displayed. 

The Commemorative Book has been compiled to celebrate 

ISRM’s 50-year anniversary by outlining the background 

to the formation of the ISRM and the most significant 

activities during the 50 years. The 2014 ISRM 

International Symposium will take place in Japan 

The ISRM Council has selected Sapporo, Japan, as the 

venue of the 2014 ISRM International Symposium, 

following a vote by secret ballot between Eurock 1014 in 

Vigo, Spain, and ARMS 8. 

ISRM ROCHA MEDAL 2013 

The ISRM Board decided at its Tokyo meeting in 

September 1981, to institute an annual prize with a view 

to honour the memory of Past-President Prof. Manuel 

Rocha. Profiting from the basis established by Prof. Müller, 

Prof. Rocha organized the first ISRM Congress and he 

was the leader that was responsible for transforming the 

international collaboration carried out in an amateurish 

way into a real international scientific association, having 

for the purpose settled the fundamental lines that have 

guided and supported the ISRM activity along the years. 

The Rocha Medal is intended to stimulate young 

researchers in the field of rock mechanics. The prize, a 

bronze medal and a cash prize, have been annually 

awarded since 1982 for an outstanding doctoral thesis 

selected by a Committee appointed for the purpose. 

The ISRM Board has decided to award the Rocha Medal 

2013 to Dr Mathew Pierce from Canada for the thesis “A 

model for gravity flow of fragmented rock in block caving 

mines” presented at the University of Queensland, 

Australia. He will receive the award at the 2013 ISRM 

International Symposium in Wroclaw, Poland. 

Two runner-up certificates were also awarded to Dr. He 

Lei, from China, for the thesis “Three dimensional 

numerical manifold method and rock engineering 

applications” presented at the Nanyang Technological 

University, Singapore, and to Dr. Andrea Perino, from Italy, 

for the thesis “Wave propagation through discontinuous 

media in rock engineering” presented at the Politecnico di 

Torino, Italy. 

MEMBERSHIP CERTIFICATES CAN NOW BE 

OBTAINED ONLINE 

ISRM members can obtain their membership certificate 

automatically online. To obtain your certificate, login using 

your member number and password, click on “My Account” 

and then on “Generate Certificate”, on the bottom of the 

page. 

A new browser window with a PDF file of your ISRM 

Membership Certificate for the last year paid. Click “Save 

file as”, in your browser to save it in your computer. 

THE WORLD LARGEST UNDERGROUND POWER- 

HOUSE WILL BE EXCAVATED SOON IN CHINA 

The world largest underground powerhouse at Baihetan 

hydropower station, Jingshajiang River, China will be 

excavated soon in the rock masses composed of tuff, 

interlayer shear weakness zones, and basalt with 

columnar-shaped joints. The measured maximum in situ 

stress is about 30 MPa. The underground powerhouse 

covers both sides of the river in the downstream direction 

and is composed of a main powerhouse, a transformer 

chamber and three surge shafts on each river bank, the 

dimensions of which are about 438m x 34/31 m x 86.7 m, 

368m x 21 m x 39.5 m, and about 50 m x 100 m, 

respectively. The total Installed generating capacity of 

the hydropower station is 16000 MW, consisted of 16 

generating sets of 1000 MW. 

”HYDROGEOLOGY FOR ROCK ENGINEERS” BY 

GUNNAR GUSTAFSON PUBLISHED BY BEFO WITH 

ISRM SPONSORSHIP 

The book “Hydrogeology for Rock Engineers” by Gunnar 

Gustafson, originaly written in Swedish, was translated 

into English and published by BeFo, the Swedish Rock 

Engineering Research Foundation, with ISRM 

sponsorship. The book can be purchased from BeFo. 

Groundwater has become a problem in construction of 

tunnels and other underground facilities in a way it has 

never been before. Tighter environmental regulations mean 

that documentation of a completely different calibre is 

now required when applying for permission to construct 

an underground facility. Greater requirements for a dry 

environment in road and railway tunnels have increased 

demands on sealing and drainage. Existing tunnels in 

metropolitan areas largely drain the rock of the available 

groundwater, and new under-ground constructions and 

tunnels can exacerbate the situation. Naturally, the 

traditional problems relating to groundwater remain, 

making construction difficult in water-conducting zones 

in poor-quality rock, and involving the risk of settlement if 

clay layers overlying the rock are drained. 



This book provides a review of our current knowledge 

about the hydro-geology of the crystalline basement, and 

explains how this can be applied in practical methods for 

use in site investigations, layout and design, as well as in 

the operation of tunnels and underground facilities. The 

work is based on research and practical experience of 

hydrogeological problems and phenomena. Much of the 

knowledge base comes from the SKB research and preinvestigation 

studies relating to final disposal for spent 

nuclear fuel. However, the aim is not to describe the 

research front as such, but rather to explain what is 

important and useful for the rock construction community 

in general. 

ISRM COMMUNICATION 

The website continues to be the main source of 

information about the Society and most benefits are offered 

to the members in a password protected members’ area. 

Members can now download their membership certificates 

in pdf format. 

The digital newsletter is sent to all ISRM members and 

subscribers every 3 months. It includes news about the 

society and other news of interest to rock mechanics. 

Contributions are welcome with short news on issues of 

general interest. 

The latest issue of the News Journal, edited by Prof. 

John Hudson and Prof. Xia-Ting Feng, has 80 pages and 

contains the annual review of the Society’s activity along 

2011 and technical articles such as a summary of the 6th 

Müller Lecture. It has been posted on the website where 

it can now be read online or it can be downloaded. 

The Digital Library, hosted by OnePetro.org, continues to be 

updated with papers from more ISRM sponsored 

conferences. It has now 22 conferences, with over 25,000 pages. 

Members can download 100 papers per year at no cost. 

RECIPIENTS OF THE ROCHA MEDAL 

1982 A.P. Cunha PORTUGAL Mathematical Modelling of Rock Tunnels 

1983 S. Bandis GREECE Experimental Studies of Scale Effects on Shear Strength and 

Deformation of Rock Joints 

1984 B. Amadei FRANCE The Influence of Rock Anisotropy on Measurement of Stresses 

in Situ 

1985 P.M. Dight AUSTRALIA Improvements to the Stability of Rock Walls in Open Pit Mines 

Calculation Model for the Behaviour of a Deep-Lying Seam 

Roadway in a Solid (but cut by Bedding Planes) 

1986 W. Purrer AUSTRIA Surrounding Rock Mass, taking into Consideration the Failure 

Mechanisms of the Soft Layer Determined In-Situ on Models 

1987 D. Elsworth UNITED KINGDOM Laminar and Turbulent Flow in Rock Fissures and Fissure 

Networks 

1988 S. Gentier FRANCE Morphology and Hydromechanical Behaviour of a Natural Fracture 

in a Granite, under Normal Stress - Experimental and Theoretical 

Study 

1989 B. Fröhlich GERMANY Anisotropic Swelling Behaviour of Diagenetically Consolidated 

Claystones 

1990 R.K. Brummer SOUTH AFRICA Fracturing and Deformation at the Edges of Tabular Gold Mining 

Excavations and the Development of a Numerical Model 

describing such Phenomena 

1991 T. H. Kleine AUSTRALIA A Mathematical Model of the Rock Breakage by Blasting 

1992 A. Ghosh INDIA Fractal and Numerical Models of Explosive Rock Fragmentation 

1993 O. Reyes W. PHILIPPINES Experimental Study and Analytical Modelling of Compressive 

Fracture in Brittle Materials 

1994 S. Akutagawa JAPAN A Back Analysis Program System for Geomechanics Application 

1995 C. Derek Martin CANADA The Strength of Massive Lac du Bonnet Granite around 

Underground Openings 

1996 M. P. Board USA Numerical Examination of Mining-Induced Seismicity 


ISRM News 

31 

1997 M. Brudy GERMANY Determination of In-Situ Stress Magnitude and Orientation of 

9 km Depth at the KTB Site 

1998 F. MacGregor AUSTRALIA The Rippability of Rock 

1999 A. Daehnke SOUTH AFRICA Stress Wave and Fracture Propagation in Rock 

2000 P. Cosenza FRANCE Coupled Effects between Mechanical Behaviour and Mass 

Transfer Phenomena in Rock Salt 

2001 D. F. Malan SOUTH AFRICA An Investigation into the Identification and Modelling of Time- 

Dependent Behaviour of Deep Level Excavations in Hard Rock 

2002 M.S. Diederichs CANADA Instability of Hard Rockmasses: The Role of Tensile Damage 

and Relaxation 

2003 L. M. Andersen SOUTH AFRICA A Relative Moment Tensor Inversion Technique applied to 

Seismicity Induced by Mining 

2004 G. Grasselli ITALY Shear Strength of Rock Joints based on the Quantified Surface 

Description 

2005 M. Hildyard UNITED KINGDOM Wave Interaction with Underground Openings in Fractured Rock 

2006 D. Ask SWEDEN New Developments of the Integrated Stress 

Determination Method and Application to the ÄSPÖ Hard Rock 

Laboratory, Sweden 

2007 H. Yasuhara JAPAN Thermo-Hydro-Mechano-Chemical Couplings that Define the 

Evolution of Permeability in Rock Fractures 

2008 Z.Z.Liang CHINA Three Dimensional Numerical Modelling of Rock Failure Process 

2009 Li Gang CHINA Experimental and Numerical Study for Stress 

Measurement by Jack Fracturing and Estimation of Stress 

Distribution in Rock Mass 

2010 J. Christer SWEDEN Rock Mass Response to Coupled Mechanical Thermal Loading. 

Andersson 

Äspö Pillar Stability Experiment, Sweden 

2011 D. Park KOREA Reduction of Blast-Induced Vibration in Tunnelling Using Barrier 

Holes and Air-deck 

2012 M.T. Zandarin ARGENTINA Thermo-Hydro-Mechanical Analysis of Joints - A Theoretical and 

Experimental Study 

Rocha Award Runner Up Certificates 

2010 Yoon Jeongseok KOREA Hydro-Mechanical Coupling of Shear-Induced Rock Fracturing 

by Bonded Particle Modeling 

2010 Abbas Taheri IRAN Properties of Rock Masses by In-situ and Laboratory Testing 

Methods 

2011 Bo Li CHINA Coupled Shear-flow Properties of Rock Fractures 

2012 B.P Watson SOUTH AFRICA Rock Behaviour of the Bushveld Merensky Reef and the Design 

of Crush Pillars 

2012 J. Taron USA Geophysical and Geochemical Analyses of Flow and Deformation 

in Fractured Rock 



PUBLICATIONS OF INDIAN NATIONAL GROUP 

PROCEEDINGS OF THE 6 TH ASIAN ROCK MECHANICS SYMPOSIUM ON “ADVANCES IN ROCK ENGINEERING” 

India is a fast developing economy requiring large scale infrastructure. Successive five year plans of Government of 

India have provided the policy frame work and funding for building up its wide infrastructure and manpower Rock 

Engineering does play an important role in most of infrastructure developmental activities related to civil engineering 

works. The need therefore is to keep ourselves abreast with the latest development in the field of rock engineering 

and its related fields such as design and construction of underground works, foundation of dams, slope stability etc. 

Keeping this in view, ISRM International Symposium and the 6 th Asian Rock Mechanics Symposium on “Advances 

in Rock Engineering” was jointly organized by the Indian National Group of ISRM and Central Board of Irrigation and 

Power, in New Delhi during 25-27 October 2010. 

The proceedings of the Symposium contains extended abstracts of 166 papers from 27 countries selected for oral 

and poster presentations on the following topics: 

• Testing and Modelling of Rocks & Rock Masses 

• Slope Stability: Analysis & Design 

• Foundations 

• Underground Structures: Analysis, Design & Construction 

• Artificial Intelligence 

• Flow and Contaminant Transport 

• Rock Dynamics 

• Techniques for Improvement of Quality of Rock Mass 

• Instrumentation and Monitoring 

In addition, the proceedings contains the full texts of the following keynote lectures delivered by renowned experts 

from Australia, Canada, China, Israel, Italy, Japan, Singapore, U.K. and USA: 

• On Site Visualization as a New Paradigm for Field Measurement in Rock Engineering 

• Progress in the Understanding of Landslides from Massive Rock Slope Failure 

• Deep Injection Disposal: Environmental and Petroleum Geomechanics 

• Application of Intelligent Rock Mechanics Methodology to Rock Engineering 

• Modelling Dynamic Deformation in Natural Rock Slopes and Underground Openings with Numerical DDA Method 

• Underground Radioactive Waste Disposal — The Rock Mechanics Contribution 

• Rock Dynamics Research in Singapore: Fundamentals and Practices 

• The Large Open Pit Project 

• Deep Underground Instrumentation and Monitoring 

The full texts are available in electronic version with the extended abstracts in print. 

MANUAL ON ROCK MECHANICS 

The first Manual on Rock Mechanics, which was prepared under the guidance of an Expert Committee, was released 

by Central Board of Irrigation & Power (CBIP) in early 1979. The manual was very well received. 

The manual was revised in 1988, to reflect the then state-of-art knowledge of Indian Engineers in the field of Rock 

Mechanics and contained 17 Chapters, covering basic concepts of Rock Mechanics, Field and Laboratory Tests on 

Rock Mass and Rock Specimen, Geophysical Investigations, Interpretation of Test Data and their Application to 

various problems of Foundation of Dams, Tunnelling, etc. 

The Governing Council of the Indian National Group of ISRM felt that there was a need to update the manual, as more 

than 20 years had passed since its last publication. 


Publications of Indian National Group 

33 

Accordingly, the manual was updated and released during the ISRM International Symposium 2010 and 6 th Asian 

Rock Mechanics Symposium held in New Delhi during 23-27 October 2010. 

The updated manual contains the following 19 chapters: 

1. Rock Mechanics – Need and Scope 

15. Design of Tunnel Lining 

2. Rock Mechanics- Basic Concepts 

16. Numerical Methods in Rock Engineering 

3. Laboratory Assessment of Rock 

17. Foundation Treatment of Dams 

4. Site Characterization – Quantitative Description 

of Discontinuities in Rock Masses 

5. Classification of Rocks Intact and Mass 

6. Geophysical Investigations 

7. Drilling for Geological Investigations 

8. Laboratory Tests for Design 

9. State of Stress in Rock Mass 

10. Field Tests for Design 

11. Devices and Instruments to Measure Movements 

and Pressures 

12. Interpretation of Test Data 

13. Rock Loads and Tunnel Supports 

14. Design of Tunnels with Rock Support Interaction 

Analysis 

18. Rock Blasting for Underground and Open 

Excavations 

19. Shotcreting, including Some Case Histories 

Members of CBIP and ISRM will be offered 10% discount. 

The proceedings can be purchased from the following 

address by payment through demand draft/cheque payable 

at par in New Delhi, in favour of “Central Board of Irrigation 

and Power”. 

Mr. V.K. Kanjlia 



Secretary 

Central Board of Irrigation & Power 

Malcha Marg, Chanakyapuri, New Delhi – 110 021, India 

E-mail:kanjlia@cbip.org; uday@@cbip.org; cbip@cbip.org 

ISRM SPONSORED FORTHCOMING EVENTS 

• 7-9 August 2012, San Jose, Costa Rica - II South American Symposium on Rock Excavations: An ISRM 

Regional Symposium 

• 15-19 October 2012, Seoul, Korea - ARMS 2012 - 7th Asian Rock Mechanics Symposium: An ISRM 

Regional Symposium 

• 20-22 May, 2013, Brisbane, Australia - Effective and Sustainable Hydraulic Fracturing - An ISRM Specialized 

Conference 

• 18-20 June 2013, Shanghai, China - SINOROCK 2013 - Rock Characterization, Modelling and Engineering 

Design Methods – An ISRM Specialized Conference 

• 20-22 August 2013, Sendai, Japan - The 6th International Symposium on Rock Stress - An ISRM Specialized 

Conference 

• 21-26 September 2013, Wroclaw, Poland - EUROCK 2013 - Rock Mechanics for Resources, Energy and 

Environment - The 2013 ISRM International Symposium 

• 26-28 May 2014, Vigo, Spain - EUROCK 2014 - Rock Engineering and Rock Mechanics: Structures in and 

on Rock Masses – An ISRM Regional Symposium 

• 15-17 October 2014, Sapporo, Japan - ARMS 8 - 8th Asian Rock Mechanics Symposium - The 2014 ISRM 

International Symposium 

• 10-13 May 2015, Montréal, Canada - ISRM 13th International Congress on Rock Mechanics 

• 7-9 October 2015, Salzburg, Austria - EUROCK 2015 – Geomechanics Colloquy - An ISRM Regional 

Symposium 



Seminar 

SLOPE STABILIZATION CHALLENGES IN 

INFRASTRUCTURE PROJECTS 

29-30 November 2012, New Delhi 

OBJECTIVE 

Slope failures are significant natural hazards in many areas throughout the world. Slope failures can be triggered by 

weather events, geologic events, human modification of the landscape, or most commonly, some interaction of all of 

the above. Mountainous regions, hilly regions, open pit mining, and coastlines have the greatest risk of slope failures. 

Also, locations in active tectonic regions are prone to slope failures triggered by earthquakes or volcanic activity. 

The objective of the proposed Seminar is to provide a forum for design and construction engineers for analyzing the 

stability of slopes of earth and rock-fill dams, other embankments, excavated slopes, and natural slopes in soil and 

soft rock, methods for analysis of slope stability, strength tests, analysis conditions, factors of safety, and use of 

geosynthetics for slope stability, etc. 

The Seminar is being organised by the Central Board of Irrigation and Power, with the support of the Indian National 

Group of International Society for Rock Mechanics and Indian Chapter of International Geosynthetics Society. 

TOPICS 

• Numerical Analysis and Design Methods 

• stability of slopes of earth and rock-fill dams 

• Acceptable Risk for Open Pit Mining 

• Early Warning Systems for Slope Failures 

• Seismic Slope Stability 

• Geosynthetics for Slope Stability 

• Performance of Different Softwares (Slope/W, Geoslope, Galena, Oasis, etc.,) 

• Case Studies 

CALL FOR CASE STUDIES 

Case studies on the topics proposed and allied topics are invited. Intending authors may send the full text of their 

case studies. The last date for the receipt of full texts of the case studies is 10 th November 2012. 

The case studies will be reviewed by the Technical Committee as to their suitability for presentations. The case 

studies accepted for presentation will be notified by 16 th November 2012. A condition of acceptance of the case 

studies will be that the author, or one of the authors in case of multiple authors, will attend the Seminar and make the 

presentation. 

REGISTRATION FEE 

Members of CBIP/IGS/ISRM INR 10,112/USD 250, including service tax 

Non-Members 

INR 11,236/USD 280, including service tax 

Students 

INR 5,618/USD 140, including service tax 

For further details, please contact: 


Secretary 

Central Board of Irrigation & Power 

Malcha Marg, Chanakyapuri, New Delhi 110 021 

E-Mail : uday@cbip.org; cbip@cbip.org 


Guidelines for Authors 

35 

GUIDELINES FOR AUTHORS 

This journal aims to provide a snapshot of the latest research and advances in the field of Rock Mechanics. The 

journal addresses what is new, significant and practicable. Journal of ISRM (India) is published twice a year (January- 

June and July-December) by Indian National Group of ISRM. The Journal has both print and online versions. Being 

peer-reviewed, the journal publishes original research reports, review papers and communications screened by Editorial 

Board. 

The original manuscripts that enhance the level of research and contribute new developments to the Rock Mechanics 

are encouraged. The journal is expected to exchange the ideas and information between Rock Mechanics practitioners 

and help researchers, technologist and policy makers in the key sectors of Water Resources, Infrastructure 

Development (including underground infrastructure), Hydro Power, Mining, and Petroleum Engineering, etc., 

to enhance their understanding of it. The manuscripts must be unpublished and should not have been submitted for 

publication elsewhere. There are no Publication Charges. 

1. Guidelines for the preparation of manuscripts for publishing in “ISRM (India) Journal” 

The authors should submit their manuscript in MS-Word (2003/2007) in single column, double line spacing as per the 

following guidelines. The manuscript should be organized to have Title page, Abstract, Introduction, Material & 

Methods, Results & Discussion, Conclusion, and Acknowledgement. The manuscript should not exceed 16 pages in 

double line spacing. 

• Take margin as 1.” (Left, Right, Top & Bottom) on A4 paper. 

• The Title of the paper should be in bold and in Title case . 

• The next item of the paper should be the author’s name followed by the co-authors. 

• Name of the corresponding author should be highlighted by putting an asterisk, with whom all the future 

correspondence shall be made. 

• This should be followed by an affiliation and complete official addresses. 

• Providing e-mail id is must. 

• Please keep the title, author’s name and affiliation center aligned. 

• Use the following font sizes: 

Title: 14 point bold (Title Case), Author’s name(s): 12-point bold, Author’s Affiliations: 10-point normal, Headings: 

11-point bold & caps, Sub-headings: 11-point normal & caps, Body Text: 10-point normal. 

• The manuscript must be in English. 

• Manuscripts are accepted on the basis that they may be edited for style and language. 

• Use Times new roman as the font. 

• Words used in a special context should appear between single quotation marks the first time they appear. 

• Lines must be double-spaced (plus one additional line between paragraphs). 

• Tables and figures must be included in the same file as the text in the end of the manuscript. Figures must be 

inserted into the document in JPEG or Tagged Image File Format (TIFF) format. 

• Abbreviations should be spelt out in full for the first time they appear and their abbreviated form included in 

brackets immediately after. 

• Communicating author will receive a soft copy of his/her published paper at free of cost. 

• Diagrams and Figures: Only black & white figures are accepted. Figures should be entered in one column (center 

aligned) and should not exceed 6-inch total width. A minimum line width of 1 point is required at actual size. 

Annotations should be in Times New Roman 12 point with only the first letter capitalized. The figure caption should 

be preceded by ‘Figure’ followed by the figure number. For example, ‘Figure 10. 

• Photographs and illustrations: No color photographs are allowed. Image files should be optimized to the minimum 

possible size without compromising the quality. The figures should have a resolution of 300 dpi. 



• Equations: Using the appropriate editor, each equation should appear on a new line. The equations referred to in 

the text, should be numbered sequentially with their identifier enclosed in parenthesis, right justified. The symbols, 

where referred to in the text, should be italicized. 

E=mc2 (1) 

• References: The papers in the reference list must be cited in the text in the order in which they appear in the text. 

In the text, the citation should appear in square brackets “[]”. References of Journals, Books and Conferences 

must be written as shown in the example below. 

o Jones B., Brown, J., and Smith J. 2005, The title of the book. 1st edition, Publisher. 

o Jones B., Brown, J., and Smith J. 2005 The title of the conference paper. Proc Conference title 6: 9-17. 

o Jones B., Brown, J., and Smith J. .2005 The title of the journal paper. Journal Name. 3(4): 101-121. 

Submission of Manuscript: 

The manuscript must be submitted in doc and pdf as an email attachment to uday@cbip.org. The author(s) should 

send a signed declaration form mentioning that, the matter embodied in the manuscript is original and copyrighted 

material used during the preparation of the manuscript has been duly acknowledged. The declaration should also 

carry consent of all the authors for its submission to Journal of ISRM (India). It is the responsibility of corresponding 

author to secure requisite permission from his or her employer that all papers submitted are understood to have 

received clearance(s) for publication. The authors shall also assign the copyright of the manuscript to the publisher 

Indian National Group of ISRM. 

Peer Review Policy 

Review System : Every article is processed by a masked peer review of double blind or by three referees and edited 

accordingly before publication. The criteria used for the acceptance of article are: contemporary relevance, updated 

literature, logical analysis, relevance to the global problem, sound methodology, contribution to knowledge 

and fairly good English. Selection of articles will be purely based on the experts’ views and opinion. Authors will be 

communicated within Two months from the date of receipt of the manuscript. The editorial office will endeavor to 

assist where necessary with English language editing but authors are hereby requested to seek local editing assistance 

as far as possible before submission. Papers with immediate relevance would be considered for early publication. 

The possible expectations will be in the case of occasional invited papers and editorials, or where a partial or entire 

issue is devoted to a special theme under the guidance of a Guest Editor. 


CBIP RELEASes JOURNALS OF 

10 ASSOCIATED Organisations 

The Central Board of Irrigation and Power, a premier organization in the field of Water Resources, Power and 

Renewable Energy Sector, also functions as the Indian National Chapter for 10 International Organizations. CBIP 

is already bringing out a monthly Journal “Water and Energy International” whereas these 10 organizations have 

recently started bringing out its half yearly Journals. The details of these journals are given as under: 

1. The Aim of these organizations is to disseminate technical information in the field of power, water resources 

and renewable energy sectors. 

2. These journals cover authoritative articles encompassing the developments of concerned sector and their 

innovative uses. 

3. These journals are effective vehicle for the exchange of information on developments in the technology and 

experience gained in the relevant field. 

4. The journals provide information related to technical events and news in India and abroad. Information 

pertaining to the activities of the concerned international organizations will be regularly highlighted. 

5. Original unpublished articles/technical papers that enhance the knowledge and expertise in the concerned 

field are encouraged. 

6. The articles/technical papers are generally peer reviewed before publication by the Editorial Board consisting 

of renowned experts. 

7. The journals have both print and online versions. 

Highly useful for 

• Public & Private Power Developers 

• Water, Power & Renewable Energy Infrastructure Companies 

• Equipment Manufacturers 

• Technical and Environmental Consultants in Water, Power & Renewable energy sectors. 

• Power Exchanges and Power traders 

• Education and Research Institutions 

• Young Professionals 

Why Need to subscribe 

• To Understand ground realities of the Indian Water, Power and Renewable Energy Sectors 

• Awareness about future developments 

• To spot investment opportunities 

• To gain the maximum advantage of the industry’s growth potential by developing strategies based on 

latest information. 

• To Facilitate decision making based on strong historic and forecast data 

• To Enhance decision making capability in a rapid and time sensitive manner 

• To Enhance the growth and expansion of these sectors. 

Subscription Rates Actual Rates After Discount 

Subscription rates for One Set of Energy Sector Journals for 1 year including Water & Energy 

International, CIGRE India, Power Engineer, AARO, IASH (Rs. 2400 + @ 600 x 4) 

Subscription rates for Set of Water Resources Sector Journals for 1 year including Water & 

Energy International, ISRM (India), IGS, IWRA, TAI, NDC-WWC, INCOLD (Rs. 2400 + @ 

600 x 6) 

Rs. 4800/- Rs. 4400/- 

Rs. 6000/- Rs. 5400/- 

Subscription rates for one Set of 11 Journals for 1 year (Rs. 2400 + @ 600 x 10) Rs. 8400/- Rs. 7400/- 

37 Volume 1 v No. 2 v July 2012

Detail of Journals 

Water Resources Sector 

1. INCOLD JOURNAL (TECHNICAL JOURNAL OF INDIAN COMMITTEE ON LARGE DAMS) 

Half-yearly issue @Rs. 600/-PA. Cheque/bank draft drawn in favour of “Committee for 

International Commission on Large Dams, India” payable at New Delhi Bank Name: 

ICICI Bank Limited, Account No. : 034601001055 

About the Journal 

• INCOLD Journal is half yearly journal published by Indian Committee on Large Dams 

(INCOLD) which is the national chapter of International Commission on Large Dams, 

with its headquarters at Paris, France founded in the year 1928 having membership of 95 

countries with approximately 10000 individual members. 

• INCOLD is involved in collection and dissemination of information on the latest 

technological developments that are taking place in the field of dam engineering and its 

related activities all over the world. 

• The aim of the journal is to provide the latest information in regard to developments that 

are taking place in the relevant field and also provide a media to encourage exchange of 

ideas on latest technological developments in the field among the dam engineering professionals. The journal shall 

also provide information on technical events taking place worldwide on the relevant subject matters, new publications, 

besides information on the activities of International as well as the Indian Committee on Large Dams. 

• The journal shall publish fully-reviewed qualitative articles on planning, design, construction and maintenance of 

reservoirs, dams and barrages and their foundations, reports of modelling of dams and associated structures, research 

work etc. 

2. TAI JOURNAL (TECHNICAL JOURNAL OF INDIAN CHAPTER OF INTERNATIONAL TUNNELLING 

AND UNDERGROUND SPACE ASSOCIATION i.e., TUNNELLING ASSOCIATION OF INDIA) 

Half-yearly issue @Rs. 600/-PA. Cheque/bank draft drawn in favour of “Adhering 

Committee of International Tunnelling Association (India)” payable at New Delhi. 

Bank Name: ICICI Bank Limited, Account No. : 034601001051 


• TAI Journal is half yearly journal published by Tunnelling Association of India which 

is the national chapter of International Tunnelling and Underground Space Association 

(ITA) with its headquarters at Lausanne, Switzerland, founded in the year 1974 having 

membership of 64 countries and 310 Corporate or Individual Affiliate Members. TAI 

is promoting advances in planning, design, construction, maintenance and safety of 

tunnels and underground space, by bringing together information thereon. 

• The aim of the journal is to provide latest information in regard to developments taking 

place in the relevant field and also provide a media to encourage exchange of ideas on 

latest underground technological developments among the engineering professionals. In addition to the above, the 

journal shall also provide information on technical events taking place worldwide on the relevant subject matters, new 

publications, besides information on the activities of International as well as the Indian Chapter of the Association. 

• The journal shall publish authoritative articles screened by the Editorial Board, encompassing the development of 

innovative uses of underground space and the results of high quality research into improved, more cost-effective 

techniques for the planning, geo-investigation, design, construction, operation and maintenance of underground 

and earth-sheltered structures. 

Volume 1 v No. 2 v July 2012 

38

3. ISRM (INDIA) JOURNAL (TECHNICAL JOURNAL OF INDIAN NATIONAL GROUP OF ISRM) 

Half-yearly issue @Rs. 600/-PA. Cheque/bank draft drawn in favour of “The Committee 

of International Society for Rock Mechanics” payable at New Delhi. Bank Name: ICICI 

Bank Limited, Account No. 034601001056 


• ISRM (India) Journal is half yearly journal published by the Indian National Group of 

International Society for Rock Mechanics (ISRM). ISRM was setup in the year 1962 

and has its Secretariat in Portugal. 

• Indian National Group of International Society for Rock Mechanics is involved in 

dissemination of information on Rock Mechanics, and its related activities in the field 

of foundation and abutments of dams, tunnel engineering, mining, underground works, 

rock slope stability, road works, etc. 

• The aim of the journal is to encourage exchange of ideas and information among Rock 

Mechanics practitioners, researchers, technologist, policy makers in Water Resources, Infrastructure sectors including 

Underground works, Hydropower, Mining and Petroleum Engineering etc. In addition, the journal also provides 

information on technical events taking place world wide on the relevant subject matters, new publications, besides 

information on the activities of International as well as the Indian National Group of the Society. 

4. INDIAN JOURNAL OF GEOSYNTHETICS AND GROUND IMPROVEMENT (TECHNICAL JOURNAL 

OF INDIAN CHAPTER OF INTERNATIONAL GEOSYNTHETICS SOCIETY) 

Half-yearly issue @Rs. 600/-PA. Cheque/bank draft drawn in favour of “The Committee 

for the IGS (India)” payable at New Delhi. Bank Name: ICICI Bank Limited, Account 

No. 034601001053 


• Indian Journal of Geosynthetics and Ground Improvement is half yearly journal 

published by the Indian Chapter of International Geosynthetics Society (IGS). IGS was 

setup in the year 1983, and has its Secretariat in USA. 

• The Indian Chapter of IGS is involved in collection and dissemination of information 

on all matters relevant to geotextiles, geomembranes and related products. 

• The aim of the journal is to provide the latest information in regard to developments 

taking place in the relevant field of geosynthetics so as to improve communication and 

understanding regarding such products, among the designers, manufacturers and users 

specially belonging to the textile and civil engineering communities. In addition, the journal shall also provide 

information on technical events taking place worldwide on the relevant subject matters, new publications, besides 

information on the activities of International as well as the Indian Chapter of the Society. 

5. IWRA (INDIA) JOURNAL (TECHNICAL JOURNAL OF INDIAN GEOGRAPHICAL COMMITTEE OF 

IWRA) 

Half-yearly issue @Rs. 600/- PA. Cheque/bank draft drawn in favour of “The 

Geographical Committee of International Water Resources Association” payable at 

New Delhi. Bank Name: ICICI Bank Limited, Account No. 034601001059 


• IWRA (India) Journal is half yearly journal published by the Indian Geographical 

Committee of International Water Resources Association (IWRA). IWRA was setup in 

the year 1971 and has its Secretariat in France. 

• Indian Geographical Committee of International Water Resources Association is 

involved in the dissemination of information in the field of water resources. 

39 Volume 1 v No. 2 v July 2012

• The aim of the Journal is to expand the understanding of water issues through information exchange, by providing 

latest information in regard to developments taking place in the field of Water Resources, primarily in India. In 

addition, the journal shall also provide information on technical events taking place world wide on the relevant subject 

matters, new publications, besides information on the activities of International as well as the Indian Geographical 

Committee of the Association. 

6. NDC-WWC JOURNAL (JOURNAL OF NEW DELHI CENTRE OF WWC) 

Half-yearly issue @Rs. 600/- PA. Cheque/bank draft drawn in favour of “New Delhi Centre 

of World Water Council payable at New Delhi. Bank Name: ICICI Bank Limited,; Account 

No. 034601001052 


• NDC-WWC journal is half yearly journal published by New Delhi Associate Centre of 

World Water Council (NDC-WWC) with its headquarters at Marseille, France founded 

in the year 1996 on the initiative of renowned water specialists and international 

organizations, in response to an increasing concern about world water issues from the 

global community. 

• NDC-WWC is promoting the efficient conservation, protection, development, planning, 

management and use of water in all its dimensions on an environmentally sustainable 

basis for the benefit of all. 

• The aim of the journal is to focus on the increasing concern on water policy issues of the Indian community. Experiences 

gained from the water sector reforms being carried-out in different states shall be informed to all concerned through 

various articles. The journal shall provide an effective vehicle for the exchange of experience and information on 

developments and management of water resources. In addition to the above, the journal shall also provide information 

on technical events taking place worldwide on the relevant subject matters, new publications, besides information on 

the activities of World Water Council (WWC) as well as the New Delhi Centre of WWC. 

WATER AND ENERGY INTERNATIONAL Monthly JOURNAL OF 

CENTRAL BOARD OF IRRIGATION AND POWER 

(Under Publication since 1936) 

Monthly Issue @Rs. 2400/- PA Cheque/bank draft drawn in favour of “Central Board 

of Irrigation and Power” payable at New Delhi. Bank Name: ICICI Bank Limited; 

Account No. : 034601000738 


• Water and Energy International Journal disseminates technical knowledge to the 

professionals and helps the country in accelerating the development of energy, 

water resources and renewable sectors. 

• CBIP is publishing this journal since 1936. 

• The monthly journal has been introduced with an objective to facilitate the 

readers getting quickly the latest information with respect to development in 

these sectors 

• The new version of Water and Energy International Journal covers technical 

articles, international and national news, Research work in these areas and developmental and dissemination 

work being carried out by CBIP. 

CBIP Invites Papers/ Articles for publishing in their Journals 

related to Energy, Water Resources and Renewable Sectors. 

Volume 1 v No. 2 v July 2012 

40

ABOUT ISRM 

The International Society for Rock Mechanics (ISRM) was founded in Salzburg in 1962 as a result of the 

enlargement of the “Salzburger Kreis”. Its foundation is mainly owed to Prof. Leopold Müller who acted as President 

of the Society till September 1966. The ISRM is a non-profit scientific association supported by the fees of the 

members and grants that do not impair its free action. The Society has 5,000 members and 46 National Groups. 

The field of Rock Mechanics is taken to include all studies relative to the physical and mechanical behaviour of 

rocks and rock masses and the applications of this knowledge for the better understanding of geological processes 

and in the fields of Engineering. 

The main objectives and purposes of the Society are: 

• to encourage international collaboration and exchange of ideas and information between Rock Mechanics 

practitioners; 

• to encourage teaching, research, and advancement of knowledge in Rock Mechanics; 

• to promote high standards of professional practice among rock engineers so that civil, mining and petroleum 

engineering works might be safer, more economic and less disruptive to the environment. 

The main activities carried out by the Society in order to achieve its objectives are: 

• to hold International Congresses at intervals of four years; 

• to sponsor International and Regional Symposia, organised by the National Groups the Society; 

• to publish a News Journal to provide information about technology related to Rock Mechanics and up-to-date 

news on activities being carried out in the Rock Mechanics community; 

• to operate Commissions for studying scientific and technical matters of concern to the Society; 

• to award the Rocha medal for an outstanding doctoral thesis, every year, and the Müller award in recognition of 

distinguished contributions to the profession of Rock Mechanics and Rock Engineering, once every four years; 

• to cooperate with other international scientific associations. 

The Society is ruled by a Council, consisting of representatives of the National Groups, the Board and the Past 

Presidents. The current President is Prof. John A. Hudson, from United Kingdom. 

The ISRM Secretariat has been headquartered in Lisbon, Portugal, at the Laboratório Nacional de Engenharia Civil - 

LNEC since 1966, date of the first ISRM Congress, when Prof. Manuel Rocha was elected as President of the Society. 

BENEFITS TO MEMBERS 

The current benefits given to ISRM members are: 

- Individual and corresponding members 

• 1 copy of the ISRM News Journal 

• ISRM Newsletter 

• Access to the members area in the website (download of Suggested Methods and Reports, Rock Mechanics 

lectures, videos, slide collection, etc.) 

• Right to participate in the ISRM Commissions 

• Registration with a 20% discount in the ISRM Congress, International and Regional Symposia and Specialised 

Conferences 

• Personal subscription to the International Journal of Rock Mechanics and Mining Sciences at a discounted 

price (see details). 

• Personal subscription to the Journal Rock Mechanics and Rock Engineering at a discounted price. 

• Free download of up to 100 papers per year from the ISRM Digital Library at OnePetro: www.onepetro.org 

- Corporate members 

• Listed in the ISRM website, with a link to the company’s website 

• Listed in the ISRM News Journal 

• Access to the members area in the ISRM website 

• ISRM Newsletter 

• 1 copy of the ISRM News Journal 

• 1 registration with a 20% discount as ISRM member in the ISRM Congress, International and Regional 

Symposia and Specialised Conferences 

• Free download of up to 250 papers per year from the ISRM Digital Library at OnePetro: www.onepetro.org


Introduction 

The study of rock mechanics has assumed considerable importance because of its wide application in civil engineering, 

more predominantly in water resources, mining engineering and underground structures. For the execution of 

multipurpose water resources projects located in complicated geological settings, the significance of rock mechanics 

in the design and construction was realised in late 1950s. Despite tremendous alround advancement in technology, a 

full understanding of natural forces and phenomena eludes the design engineer. Liberalisation of economy has facilitated 

planning and execution of many exciting and complicated projects. These projects require application of modern 

principles of rock mechanics, which warrants deliberations and collaboration to facilitate flow of appropriate technology 

to enable successful implementation of such projects under a time-bound programme in a cost-effective manner, 

conforming to environmental requirements. 

The Indian National Group of ISRM - ISRM (India) is involved in dissemination of information regarding rock 

mechanics, mining and tunnel engineering by organising symposia, seminars, workshops, and training courses, 

both at national as well as international level, in liaison with international organisations. 

ISRM (India) represents International Society for Rock Mechanics, founded in Salzburg in 1962, as its Indian National 

Group. 

Objectives 

• to encourage collaboration and exchange of ideas and information between rock mechanics practitioners in the 

country 

• to encourage teaching, research and advancement of knowledge in the rock mechanics 

• to promote high standards of professional practice among rock engineers so that civil, mining and petroleum 

engineering works might be safer, more economic and less disruptive to the environment 

• to hold events periodically on rock mechanics and rock engineering themes of general interest to the majority of 

the membership 

• to cooperate with international bodies whose aims are complementary to those of the society 

• to encourage the preparation of internationally recognized nomenclature, codes of practice, standard tests and 

procedures 

• to encourage collaboration with and support of international programme in the field of Rock Mechanics including 

cooperation with other organizations in the activities of common interest 

• to act as a coordinating National Body of International Society of Rock Mechanics, comprising of members in the 

country concerned with Rock Mechanics 

Membership Fee 

• Individual Membership for one calendar year: Rs. 600.00 

• Individual Membership for 10 calendar years: Rs. 6,000.00 

• Individual Membership for 20 calendar years: Rs. 10,000.00 

• Institutional Membership for 01 calendar year: Rs. 10,000.00 

• Institutional Membership for 02 calendar years Rs. 18,000.00 



For membership and other details, please contact: 



International Society for Rock Mechanics (India) 

C/o Central Board of Irrigation and Power 

Plot No. 4, Institutional Area, Malcha Marg, Chanakyapuri, New Delhi 110 021 

Phone : 91-11-2611 5984/2611 1294, Fax : 91-11-2611 6347 

E-mail : uday@cbip.org/kanjlia@cbip.org/cbip@cbip.org

ISSN : 2277-1328 (Online) - ISRM

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