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<strong>NGI</strong> annual OTC<br />

reception<br />

The best opportunity at OTC to meet<br />

friends and colleagues from the<br />

geosciences!<br />

8. May 2013 at ZaZa


<strong>NGI</strong> organization<br />

Managing Director<br />

Lars Andresen<br />

Ingrid Malnes<br />

Kjell Karlsrud, Knut H. Andersen,<br />

Farrokh Nadim<br />

Finance and Accounting<br />

Mimoun Bouhmidi<br />

HR and Information<br />

Inger Kristine Tovslid<br />

Quality Assurance and HSE<br />

Geraldine Sørum<br />

IT Services<br />

Stein Strandvik<br />

Subsidiary<br />

<strong>NGI</strong> Inc. (USA)<br />

Audun Hauge<br />

Technology innovation<br />

James Michael Strout<br />

Offshore Energy Environmental Engineering Natural Hazards Building, Construction and Transport.<br />

Karl Henrik Mokkelbost Anne Kibsgaard Anders Solheim Ørjan Nerland<br />

Offshore Geotechnics<br />

Thomas Langford<br />

Water and Resources<br />

Arne Pettersen<br />

Avalanches and Rock Slides<br />

Ulrik Domaas<br />

Onshore Foundations<br />

Magnus Rømoen<br />

Instrumentation and Monitoring<br />

Dag Tollefsrud<br />

Contaminants and Land Use<br />

Paul Sverdrup Cappelen<br />

Debris Slides and Georisk<br />

Bjørn G. Kalsnes<br />

Field Investigations<br />

Kristoffer Kåsin<br />

Petro.Geomech. and –physics (PGG)<br />

KH Mokkelbost<br />

Geomapping<br />

Andreas Aspmo Pfaffhuber<br />

<strong>NGI</strong> Trondheim<br />

Randi Skirstad Grini<br />

Computational Geomechanics<br />

Karin Norèn-Cosgriff<br />

Eng. Geology and Rock Mech.<br />

Roger Olsson<br />

Laboratory and Model Testing<br />

Morten Andreas Sjursen


Some practical issues<br />

• Safety<br />

• Parking validation<br />

• Email addresses & invitations + name tags<br />

The Boss<br />

Dewey, Cheetum and Howe<br />

59 Estreet


Your hosts this afternoon<br />

From <strong>NGI</strong> inc<br />

Audun Hauge<br />

Knut Schrøder<br />

Francisco Hernandez-Martinez<br />

Young Jae Choi<br />

Amir Rahim<br />

Victor Taboada<br />

Gokhan Saygili<br />

From <strong>NGI</strong><br />

Lars Andresen<br />

Suzanne Lacasse<br />

Maarten Vanneste<br />

James (Jim) Strout<br />

Øyvind Torgersrud<br />

Dag Tollefsrud<br />

Morten Saue<br />

Thomas Langford<br />

Karl Henrik Mokkelbost


Topics this afternoon<br />

<br />

<br />

<br />

<br />

<br />

Time effects on piles – outcome from JIP<br />

Schmertmann Research lab – operating<br />

Earth Quake loads on pipelines<br />

Offshore wind<br />

<br />

Proposal for new JIP on piles<br />

<br />

Final remark


From onland and offshore geotechnics<br />

Time effects on pile capacity<br />

A JIP project organized by <strong>NGI</strong><br />

Work by Dr Kjell Karslrud


Objective: Establish practical design<br />

procedures that account for effects of time<br />

on the axial bearing capacity of piles<br />

Elements:<br />

‣ Collect and sumarise available data on time effects axial bearing<br />

capacity<br />

‣ Perform new pile load tests in the field, with specific focus on time<br />

effects:<br />

• 6 test sites<br />

• Pile tested: Open pipe piles, typically D=400 mm, L= 20 m<br />

‣ Develop new design procedures<br />

‣ Disseminate results to ensure that they get incorporated into<br />

national and international design guidelines and codes


Selected test sites<br />

1. Normally consolidated medium plastic clay – Onsøy ,Norway<br />

2. Normally consolidated low plastic clay, Stjørdal, Norway<br />

3. Stiff overconsolidated low plastic clay, Cowden UK<br />

4. Highly plastic OC clay in the sea at Femern, German coast<br />

5. Loose sand, Larvik, Norway<br />

6. Medium dense sand, Ryggkollen near Drammen, Norway


Load testing program at each site<br />

1(2)<br />

3(4)<br />

6(8)<br />

12<br />

24<br />

Pile<br />

No.<br />

Months<br />

Months<br />

Months<br />

Months<br />

Months<br />

1 x x x x x<br />

2 x x x x<br />

3 x x x<br />

4 x x<br />

5 x<br />

6 x Sust.<br />

at<br />

60%<br />

Sust.<br />

at<br />

60%<br />

x


Some of the key findings<br />

‣ The results confirm a significant ageing effect.<br />

‣ For piles in clay the effect reduces with increasing<br />

plasticity index and OCR of the clay.<br />

‣ For piles in sand the ageing effect seems in general<br />

to be even larger than in clay! The capacity may<br />

double over a two year period.<br />

‣ Repeated load testing on the same pile gives an<br />

incorrect picture of ageing effects.<br />

‣ Still possible to join the JIP – there are more work<br />

and more info that can be extracted from the program<br />

Work by Dr Kjell Karslrud


Schmertmann Research lab (SRL) – running


New Carbon fibre triaxial cell for tests in CT scanner<br />

New carbon cell that allows for anisotropic<br />

consolidation of rock plug<br />

X-ray imaging of rock core and saturation<br />

during flow and deformation testing<br />

• Main Features<br />

• Sample dimension 38 mm diameter, 100 mm length<br />

• Axial load 100 kN (88 MPa on 38 mm sample)<br />

• Radial confinement: 70 MPa<br />

• Pore pressure: 70 MPa<br />

• Working temp. 140 deg C<br />

• Suitable for corrosive fluids<br />

• Balanced piston or external load frame.<br />

• Axial Vp, Vs, and R<br />

• Axial and radial strain measurements<br />

• 12 radial acoustic pinducers, fittings for 25 mm samples<br />

New


New direct shear box for testing on fractured material<br />

<br />

<br />

<br />

<br />

For testing of intact or fractured rock<br />

Measure direct shear strength, friction and<br />

deformation behavior<br />

Conductivity of fracture during normal<br />

stress and shear at high stresses<br />

Applications related to CO2 storage and<br />

testing of shale gas<br />

Main Features<br />

• Max specimen dimensions 150x150x300 mm.<br />

• Max shear force: 250 kN<br />

• Max shear displacement: 100 mm<br />

• Max normal force: 500 kN<br />

• Max pore pressure: 2 MPa<br />

• Max flow gradient: 4 MPa<br />

• Future option for ultrasonic velocity transducers<br />

Test on<br />

Natural<br />

Fracture in<br />

shale<br />

Before test<br />

After test


CGM<br />

Pipelines under earthquake-induced soil movements<br />

• Pipelines traversing slopes are<br />

subjected to down slope movements<br />

of slopes during earthquakes.<br />

• In moderate to steep slopes in deep<br />

water one could expect down slope<br />

displacements larger than 1 m under<br />

even moderate earthquake events.<br />

• As part of JIP (Earthquake Effects in<br />

Deep Water) at <strong>NGI</strong> a solution has<br />

been developed for computing forces<br />

in pipelines over slopes. The solution<br />

is based on computing accelerations<br />

along the slope, and applying them to<br />

3-D FE model of pipeline supported<br />

on strain-softening springs.<br />

Contours of permanent displacements<br />

Deformations due to earthquake<br />

Work by Amir Kaynia


Sample results of<br />

analyses<br />

Maximum forces along<br />

pipeline during<br />

earthquake<br />

Maximum axial force (kN)<br />

2 500<br />

2 000<br />

1 500<br />

1 000<br />

500<br />

0<br />

-500 0 500 1 000 1 500 2 000 2 500<br />

Distance along pipeline (m)<br />

Maximum bending<br />

moment along pipeline<br />

during earthquake<br />

Max. bending moment (kNm)<br />

80<br />

70<br />

60<br />

50<br />

40<br />

30<br />

20<br />

10<br />

0<br />

-500 0 500 1 000 1 500 2 000 2 500<br />

Distance along pipeline (m)<br />

Work by Amir Kaynia


From Offshore geotechnics<br />

Offshore wind energy development – North Sea<br />

<strong>NGI</strong> projects include the last 10 years:<br />

<br />

<br />

<br />

<br />

Classic soil investigations<br />

Laboratory testing<br />

Foundation design for jackets and<br />

Gravity base towers<br />

Studies on foundation types.<br />

More info OWF Thursday morning<br />

Morten Saue Key note at OTC<br />

Dolwin 2, Aibel


Dolwin 2, Aibel


Subsea Leak Detection (SLD) system<br />

In place overview


Concept:<br />

Modular instrument node on subsea network<br />

Lifting yoke<br />

with Imenco connector<br />

“Mobile”<br />

Instrument<br />

module<br />

In operation<br />

Bullseye<br />

Parking slots<br />

for ROV stabs<br />

“Permanent”<br />

Seabed frame


Instrument Module<br />

Not visible in this image:<br />

sensors for measuring<br />

dissolved methane<br />

Horizontal<br />

Scanning<br />

Sonar head<br />

Vertical<br />

Scanning<br />

Sonar head<br />

Parked<br />

Aquadopp<br />

Current meter


Prototype system installation<br />

Seabed frames<br />

Monitoring modules and riser umbilical<br />

Docking Instrument module to seabed frame<br />

Hooking up COM and power line<br />

“Watch tower” on duty<br />

Subsea images: DeepOcean (responsible for installation)<br />

Subsea image: Stinger Technology AS<br />

PM at <strong>NGI</strong> was Dag Tollefsrud<br />

Jim Strout


NEW JIP on pile design??<br />

Suzanne has some ideas on that!


Proposal for a JIP<br />

Reliability of API, <strong>NGI</strong>, ICP, UWA and Fugro<br />

Axial Pile Capacity Calculation Methods<br />

• A joint effort<br />

• Needs sponsorship


Motivation<br />

• In our designs, we need to ensure the same level<br />

of safety for the new pile capacity (read CPT)<br />

methods as for the API method.<br />

• The designer is required to select an appropriate<br />

safety factor when using the CPT methods.<br />

• One can choose to be conservative and apply a<br />

“high” safety factor, or one can document the<br />

level of safety and “calibrate” the required safety<br />

factor(s) that ensures a target level of safety.


Motivation<br />

The industry needs<br />

• Guidelines on the safety factor to use with the<br />

”newer” CPT methods.<br />

• A consensus on the model uncertainty in the methods<br />

(will reduce the uncertainty and thereby reduce the<br />

probability of failure).<br />

• The most cost-effective design as possible for piles<br />

(e.g. reduce pile penetration depth where possible).


Three targets<br />

• Calibration of material factor for enough case studies<br />

so that one can generalise conclusions (OTC paper<br />

gives results for two sites that are site-specific)<br />

• Consensus on pile load test database, and<br />

publication of the database on the web<br />

• Transfer conclusions to design guidelines (API,<br />

ISO/OGP)


Modus operandi - Operator and ”expert ” involvement<br />

Calibration of safety factor(s)<br />

3-4 sites mainly clays; 3-4 sites mainly sand;<br />

3-4 sites intermixed; 2-4 sites w/ ”unusual” cond.<br />

Each sponsor to provide 2-3 case studies<br />

Sponsors can send own staff to <strong>NGI</strong> to do analyses for their<br />

own case studies<br />

Consensus on pile load test database and web publication<br />

Start with UWA’s careful work<br />

Find new large dia pile load tests<br />

Panel of experts (e.g. Jardine, Lehane, Jeanjean, Gilbert,<br />

Senders, Frimann Clausen etc) to accept/reject load<br />

tests to be included in ”consensus database”<br />

(parameters, interpretation of pile load tests, backcalculation).<br />

Job is not done until we have agreement.<br />

Complete the work in first 2 ½ years of 4-yr project.


Deliverables<br />

Calibration of material factor<br />

• 14-16 case studies (3 already done)<br />

• Method and examples<br />

‣Quantify uncertainties in soil parameters<br />

‣Quantify model uncertainty, including how to include<br />

uncertainty for large pile diameters, low plasticity, etc<br />

‣Uncertainties in effects of cyclic loading and of time on<br />

pile capacity<br />

‣Uncertainty in pile capacity and P f<br />

‣Calibration of safety factor(s).


Deliverables<br />

Consensus on pile load test database<br />

• No more discussion on which test gave what result,<br />

on ”our interpretation is more reliable than yours”!<br />

• Flexible database where on can include new pile<br />

load tests<br />

• Solution for the custody of web site and database<br />

after the JIP is completed


Proposed budget and sponsorship<br />

Budget<br />

• Calibration of material factor<br />

USD 2,2 M over 4 years<br />

• Consensus on pile load test database<br />

USD 1 M over 2 ½ years<br />

Sponsorship<br />

• 8 sponsors @ USD 100,000/yr × 4 yrs or<br />

• 10 sponsors @ USD 80,000/yr × 4 yrs<br />

Next step


<strong>NGI</strong> Inc – Change of President<br />

Knut Schrøder 2002 – 2008<br />

Stein Strandvik 2008 – 2010<br />

Audun Hauge 2010 – 2013<br />

Morten Saue 2013 ->

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