RESEARCH PROJECT TU DELFT; BEHAVIOUR CONVENTIONAL ...

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2004 Orthotropic Bridge Conference, Sacramento, California, USA – August 25-27, 2004 

RESEARCH PROJECT TU DELFT; BEHAVIOUR CONVENTIONAL BRIDGE 

DECKS & DEVELOPMENT OF RENOVATION TECHNIQUES 

F.B.P.de Jong*, M.H.Kolstein** and F.S.K.Bijlaard*** 

*Civil Engineer, Delft University of Technology, P.O.Box 5048, 2600 GA, Delft, 

The Netherlands; Phone +31-15 278 57 16; f.b.p.dejong@citg.tudelft.nl and Ministry 

of Transport, P.O.Box 59, 2700 AB, Zoetermeer, The Netherlands; Phone +31 – 79 

329 25 19; f.b.p.dejong@bwd.rws.minvenw.nl **Senior Research Engineer, Delft 

University of Technology, P.O.Box 5048, 2600 GA, Delft, The Netherlands; Phone 

+31-15 278 40 05; m.h.kolstein@citg.tudelft.nl ***Professor of Steel Structures, 

Delft University of Technology, P.O.Box 5048, 2600 GA, Delft, The Netherlands; 

Phone +31-15 278 16 75; f.s.k.bijlaard@citg.tudelft.nl 

Abstract 

In order to develop solutions for the fatigue problems in several bridges a research 

program has been started a few years ago at Delft University of Technology. The aim 

of this program is to gain more understanding of the fatigue behaviour of orthotropic 

bridge decks with respect to deck plate cracking, and also to develop long term 

renovation techniques for bridge decks with fatigue cracks. 

To obtain more insight in the behaviour of conventional orthotropic steel 

bridge decks a lot of static experiments have been performed on a realistic bridge 

deck sample in the Lintrack, a heavy vehicle simulator with a moving wheel load. 

These tests are in fact a realistic simulation of heavy vehicle traffic on highways. In 

the experiments strain distributions are measured, therefore approximately 150 strain 

gauges are applied at several locations at the test panel; both at the steel as at the 

surfacing. Experiments are performed without and with two different wearing 

courses, four wheel types, two wheel loads, two velocities and three different 

temperatures in order to achieve understanding of the influence of these parameters. 

To obtain more insight in the fatigue behaviour and to derive a detail 

classification a serie of fatigue tests have been performed. This paper describes the 

test set up and results. The results are compared with crack growth models based on 

fracture mechanics. Besides this fatigue test also a static test has been performed to 

investigate the stress patterns in the deck plate as function of the wheel load, and the 

size of the footprint. 

To deal with the fatigue problems in the future a new kind of maintenance 

philosophy has been developed for bridge decks. Essential parts of this philosophy 

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©Copyright 2004 Bouwdienst Rijkswaterstaat and University of Technology Delft



are lifetime calculations, inspection techniques and renovation techniques. The 

fundamentals of this philosophy are described in brief. 

Outline research program 

In the past a lot of orthotropic steel bridge decks have been build. The vast majority 

of these bridges in the Netherlands is build up between 1960 en 1980. Figure 1 shows 

the construction of this type of bridge, with two frequently observed, fatigue cracks. 

Fatigue phenomena are known as one of the most devastating problems for this kind 

of bridges in the Netherlands. A well-known example of a bridge suffering from 

fatigue is the Bascule Bridge Van Brienenoord in the harbour of Rotterdam (De Jong, 

2003-a). Various crack types have already been detected in several bridges. For a 

description of these cracks see (Leendertz, 2003) or (De Jong, 2004-b). As the fatigue 

cracks are induced by the amount of traffic and the heavy axle loads, fatigue 

problems will arise even more in the future. Bridge owners have to expect a lot of 

bridges with fatigue cracks in the next future. The cracks occur both in decks with a 

thin surfacing and decks with a thick asphaltic surfacing, asphalt only lowers the 

crack growth rate (De Jong, 2004-b). 

Bridge owners generally want the time spended to maintenance as less as 

possible, still remaining the required safety level. The maintenance strategy must be: 

maximizing availability, minimizing maintenance. Given this strategy the need for 

long term renovation techniques for orthotropic steel bridge decks with fatigue cracks 

is obvious. A research program to develop these renovation techniques is started at 

Delft University of Technology. The objective of the research is to develop some 

long-term renovation techniques, which are able to fulfil another lifetime of 

approximately 25 years without serious maintenance activities. The research is split 

up into a few parts, which will be revealed in this paragraph. 

After the problem definition and determination of the research objectives 

several renovation techniques have been designed which might possibly form 

solutions for the fatigue problems. Because influencing traffic properties (decreasing 

axle loads and traffic flow) is outside the scope of this research and in practice hardly 

to achieve, the designed renovation techniques are intended to reduce the stress range 

by modifying the construction of the bridge deck. 

Examples of designed renovation techniques are replacing the asphaltic 

surfacing by high strength concrete, where the concrete is bonded to the original steel 

deck plate. This method might be very useful for fixed bridges, because the majority 

of fixed bridges is supplied with an asphaltic surfacing. Instead of high strength 

concrete an aluminium extrusion profile could be bonded to the original steel deck 

plate, also an appropriate method for fixed bridges. In general renovation techniques 

can have the same thickness as the asphaltic surfacing that can be removed. Figure 2 

shows at the left side a typical cross-section of a steel deck plate with a widely used 

mastic asphaltic surfacing. On the right side it shows an aluminium extrusion profile 

as an example of a renovation technique. Bonding a second steel plate to the old steel 

plate in the heavy vehicle lane is one of the designed techniques for renovation of 

movable bridges. Limitation of extra weight due to the renovation is important 

because the constructions are not designed for increase of weight in the future. 

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After completion of the design stage the designed renovation techniques must 

be investigated both numerical and experimental. This is necessary to achieve insight 

in the mechanical behaviour as well as insight in the fatigue behaviour of the 

renovated bridge decks. Within the experimental part of the research program 

emphasis will be made on static tests and fatigue tests. The experimental work is 

partly done in the laboratory and partly done in the Lintrack, a heavy vehicle 

simulator. The experiments in the Lintrack are a major part of the research project 

(De Jong, 2002, De Jong, 2004-a ). 

In the last phase of the project the designed renovation techniques will be 

evaluated, based on the numerical and experimental work. The results of this phase 

are design procedures and recommendations for renovations for steel bridge decks. 

Behaviour orthotropic bridge decks 

Test purpose. Within this research project strain measurements on a realistic bridge 

deck panel have been carried out with a heavy vehicle simulator, thus creating test 

conditions that are more in accordance with the situation on the motorways as in a 

laboratory. 

Determination of stress and strain distribution under real moving wheel loads 

in deck plate, trough wall and surfacing in conventional orthotropic steel bridge decks 

is in general the purpose of the first test serie in the Lintrack. Conventional bridge 

decks in the Netherlands have a deck thickness of 10 mm, and the centre-to-centre 

distance between the trough webs is usually 300 mm. Furthermore almost every fixed 

bridge is supplied with a layer of 50 mm mastic asphalt. The experiments are 

performed without and with two different surfacing layers, four wheel types, two 

wheel loads and three different temperatures in order to achieve understanding of the 

influence of these parameters. The tests are intended to obtain a better insight in the 

behaviour of conventional orthotropic steel bridge decks, especially about the strains 

at the level of the deck plate. 

The reported tests are also called benchmark experiments. At a second 

comparable test panel renovation techniques will be applicated thus representing 

renovated bridge decks. Identical test as those forming the benchmark experiments 

will be conducted at this second renovated test panel, in this way enabling a 

comparison between unrenovated and renovated bridge decks. The comparison is 

intended to quantify the stress and strain reduction at crack locations due to the 

application of the renovation technique. The second test serie is not yet performed. 

The tests are performed on a realistic bridge deck sample in the Lintrack, a heavy 

vehicle simulator, thus being a realistic simulation of heavy vehicle traffic on 

highways. 

Test panel. For the benchmark tests in the Lintrack a conventional standard 

orthotropic steel deck with a thin steel deck plate of 10 mm was available. The 

thickness of 10 mm was chosen because almost every fixed bridge in the Netherlands 

has this deck plate thickness. Figure 3 comprises among other things a technical 

drawing of the test panels. The distance between the transverse crossbeams is 2 m, 

while in practice 4 m is a regular distance. This distance was shortened in the test 

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specimens to create more crossings between crossbeam and trough profile. The 

crossbeams are continuously supported, while in bridges they are only supported by 

the main girders. These are two significant differences between the test panels and 

real bridges, but for the research reported irrelevant because this is pointed towards 

fatigue problems at deck plate level. The sections of the test panel are supplied with 

two different surfacings; in section 1 a layer of 50 mm conventional mastic asphalt 

and in section 2 a layer of 50 mm ZOK, which is an open graded polymer based 

surfacing. ZOK is a new type of surfacing, which is used a few times up to now. 

Testing facility. The tests have been conducted in the Lintrack, a heavy vehicle 

simulator originally build up for pavement testing (Groenendijk, 1998). The Lintrack 

gives the possibility of simulating real traffic on bridge decks. Figure 4 shows a side 

view of the Lintrack. Basically it is an apparatus with a moving wheel load. The load 

can be varied between 15 en 100 kN, the velocity between 0 en 20 km/h. Different 

tyres can be mounted to the axis. Besides the movement in longitudinal direction, 

movements in lateral direction are possible to enable the creation of influence 

surfaces and gaussian distribution of the wheel loads in pavement testing. The 

Lintrack facility is equipped with a heating installation in order to control the 

temperature of tested pavement material. 

Instrumentation. Approximately 150 strain gauges are applied at several locations at 

the test panel, which measure the strain in transverse direction; at the top and bottom 

of the steel deck plate, at the web of the trough, at the top of the intermediate layer 

between steel deck plate and surfacing layer and at the topside of the surfacing. In 

both sections similar sets of gauges are attached to several crossbeams and fields 

between the crossbeams. The strain gauge measurements have been done with a 

sample rate of 250 Hz. The location of the strain gauges is extensively described in 

Stevin Report 6.03.6 (De Jong, 2003-b) 

Testing program. The essence of all tests is measuring strains to produce influence 

lines and surfaces for the strain gauges. The benchmark experiment is basically a 

serie of identical tests, in which a few parameters are varied. These parameters are the 

wheel load, the wheel type, the velocity of the wheel, the presence and temperature of 

the surfacing. Table 1 summarizes the parameters involved. The wheel types are 

according to Eurocode 1991:2-2003, except the super super single. This wheel is a 

new developed wheel type with a width of approximately 50 cm. 

Table 1. Parameters Lintrack bench mark tests 

Wheel load Wheel type Velocity Surfacing 

25 kN A - Single 0 km/h No surfacing 

50 kN B - Double 2 km/h Surfacing 0° C 

C - Super Single 20 km/h Surfacing 15° C 

D - Super Super Single 

Surfacing 30° C 

The influence lines and surfaces are obtained for all reasonable combinations 

of the parameters. The experiments are performed before and again after the 

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application of the surfacings. The testing program is executed both in section 1 

(Mastic asphalt) as well as in section 2 (ZOK). The wheel loads have been chosen on 

basis of wheel load measurements in Dutch motorways (Vrouwenvelder, 1998, 2000- 

a, 2000-b). The two chosen loads cover the part of the axle loads, which produces the 

fatigue damage for a large extent. The wheel types are usually tyres for heavy 

vehicles, except the super super single. 

Test results. Influence surfaces have been created. The aim of the analyses is to draw 

conclusions about the influence of wheel type, wheel load, temperature and the 

velocity of the wheel on the stress pattern and stress level in the bridge deck 

construction; the differences between a bridge without surfacing, a bridge deck with 

asphaltic surfacing and a bridge deck with a ZOK surfacing; the composite action 

between the steel deck plate and the surfacing layer; the reliability of the 

measurements. 

The results are presented for two locations. These are detail B, the deck plate at 

the intersection trough wall-crossbeam, and detail A, the longitudinal weld between 

trough and deck plate. Figures 5 and 6 present two influence surfaces. Information is 

in the upper left corner of each influence surface. Both are surfaces for strain gauge 

S33 that is mounted at the topside of the deck plate near the location of fatigue detail 

B. The longitudinal position is measured from crossbeam 1. The transverse position 

varies between –450 and 450 mm. For section 1 (mastic asphalt), 0 mm is the left 

web of trough 2, for section 2 (ZOK), 0 mm is the right web of trough 5, see figure 3. 

For an extensive description of the test set up and results see (De Jong, 2003-b, De 

Jong, 2003-c and De Jong, 2004-a). 

With respect to the reduction of the strains due to the two surfacing types at 

three different temperatures the reduction percentages of the strains in the steel 

construction are derived. The reduction is in comparison with a bridge deck without 

surfacing. The reduction percentages are summarized in Table 2. The reduction 

percentages are valid for the transversal strains in deck plate (detail B) and trough 

wall (detail A) at the location of the longitudinal weld between trough and deck plate. 

Table 2. Reduction percentages due to surfacing 

Deck plate Trough wall 

Detail B Detail A 

No surfacing (reference) 0% 0% 

Mastic asphalt app. 0 °C 70-80% 50% 

Mastic asphalt app. 15 °C 20-30% 20-30% 

Mastic asphalt app. 30 °C 0-10% 0-10% 

ZOK app. 0 °C 80-90% 50-70% 

ZOK app.15 °C 60-70% 40-50% 

ZOK app. 30 °C 50% 30-40% 

Besides these reductions due to surfacing the following conclusions can be drawn 

from the tests at the Lintrack. 

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1. The strains due to wheel A are approximately the same as the strains due to 

wheel C. Strains under wheels B en D are smaller compared to strains under 

wheel C. This is the effect of mainly the width of the footprint. The larger the 

footprint the smaller the strain at the same load level. 

2. Halve the load does not mean halve the strains. Due to a smaller footprint 

by a smaller load, the load is more concentrated, causing relatively higher strains. 

3. A velocity up to 20 km/h does not significantly influence the strains. 

4. Both surfacing materials are sensitive to temperature differences, but mastic 

asphalt is more temperature sensitive then ZOK. 

5. The strains in the steel deck plate are approximately the same for the cases 

no surfacing and mastic asphalt at app. 30°C. This indicates that the usual 

modelling with a spread-to-depth ratio is less valid for surfacings. 

Static and fatigue behaviour deck plate location 

Introduction. Besides the experiments in the heavy vehicle simulator Lintrack, there 

are also experiments performed on smaller test panels in the laboratory. The 

laboratory experiments are also intended for validation of renovation techniques. 

Experimental validation should simulate the application of renovation techniques on 

bridges as best as possible. For these reason a few smaller orthotropic test panels are 

available for application of the renovation techniques. After application of the 

renovation techniques the test panels will be subjected to fatigue tests in order to 

determine the behaviour of renovated bridge deck structures. 

The research project focuses on deck plate cracks, for two reasons. First, deck plate 

cracks are often observed in highway bridges in the Netherlands. Second, this crack 

type makes bridge renovation on a large scale necessary. The fatigue tests focus on 

deck plate cracks at the intersection trough-crossbeam, the DPS01 crack. This crack 

type was for the first time detected at the Van Brienenoord Bridge in 1997 (De Jong, 

2003-a). 

A laboratory simulation consists of four phases: 

1. The unrenovated bridge deck test panel is subjected to a fatigue test in order to 

create fatigue cracks in the deck plate 

2. The fatigue cracks are repaired if necessary 

3. The renovation method is applicated to the bridge test panel 

4. The renovated bridge deck test panel is subjected to static and fatigue tests in 

order to obtain insight in the behaviour of the renovated structure. 

This paper only describes phase 1, the fatigue tests. 

Test purpose. The static and fatigue tests on laboratory test panels have four 

purposes. 1. Creating deck plate fatigue cracks. 2. Derive a Wöhler detail 

classification for the DPS01 crack. 3. Obtaining crack growth information both in 

vertical and in longitudinal direction. 4. Determine stress patterns in the deck plate at 

the crossing trough-crossbeam. 

Creating DPS01 deck plate fatigue cracks is the main purpose in phase 1. This 

test is an opportunity to obtain more information about the static and fatigue 

behaviour of this detail. Based on this new information a Wöhler classification can be 

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derived. Moreover the crack growth is monitored, which results in a crack growth 

relation, for crack growth in longitudinal direction after the crack is grown through 

the deck plate. The test gives also the possibility to determine accurate stress patterns 

in the deck plate at the crossing trough-crossbeam. 

Realistic simulation of the vertical crack growth is possible. In the phase of 

longitudinal crack growth small differences between the situation in the laboratory 

and real traffic conditions can occur, because an eccentricity between the location of 

the test load and the location of the maximum stress increases when the crack length 

grows. 

Test panels. Two test panels have been subjected to laboratory tests. Test panel A is 

given in figure 7. Test panel B is given in figure 8. Panel A is 2 * 2 m, panel B is B 2 

* 4 m and has two crossbeams in stead of one as in panel A. The deck plate thickness 

for both panels is 10 mm. Both panels have three trapezoidal trough profiles 2/325/6, 

with a centre-to-centre distance of 600 mm. Panel A has one crossbeam, panel B has 

two crossbeams. Panel A is initially used for the static test to determine stress 

patterns and subsequently for fatigue tests. Panel B is only used for fatigue tests. 

Panel A has 6 locations, and panel B has twelve locations where the DPS01 crack is 

possible. In total 18 DPS01 cracks have been created. 

Testing program. The measurements of the static strain patterns are performed for 11 

different footprints on the middle trough of panel A. Each footprint has a different 

load. The length and width of these footprints are based on the measured footprint 

areas in earlier tests (Kolstein, 2000, De Jong, 2003-c). Table 3 summarizes the width 

and length for each test and the load that has been used. Width and length of the 

footprint are in transversal and longitudinal direction of the trough profile. 

Table 3. Testing program static tests panel A 

Test nr. Width (mm) Length (mm) F (kN) 

BA1_S1 220 180 31 

BA1_S2 220 250 34 

BA1_S3 220 320 38 

BA1_S4 250 160 35 

BA1_S5 250 220 39 

BA1_S6 250 270 42 

BA1_S7 250 320 45 

BA1_S8 270 320 49 

BA1_S9 280 180 40 

BA1_S10 280 240 44 

BA1_S11 430 170 59 

Figure 9 gives the strain gauges at the deck plate of trough 2, which are used for the 

static tests. All strain gauges measure the strains in transverse direction. The fatigue 

tests have been performed with different loads. The applied loads are given in Table 

4. The load is applied on a load area of 270 mm by 320 mm. (width * length). During 

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the fatigue test the strains have continuously been measured with the attached strain 

gauges. 

Table 4. Applied loads fatigue tests panel A and B 

Test nr. Description 

Fmin (kN) Fmax (kN) Range (kN) R-ratio 

C & B Panel A trough 1 5 68.78 63.78 0.073 

E & F Panel A trough 2 5 69.30 64.30 0.072 

A & D Panel A trough 3 5 69.01 64.01 0.072 

br202 Panel B crossbeam 1 trough 1 5 80.27 75.27 0.062 



br-08 Panel B crossbeam 2 trough 1 5 93.76 88.76 0.053 



Static test results. For the static tests the measured strain signals have been 

graphically presented for various defined lines. The lines are given in figure 9. This is 

done for all the footprint sizes. In this paper the graphical results are given for the 

lines A-A and G-G, for footprint nr 8. (270 * 320 mm). See figure 10 and 11. 

The figures also include analytical results. For the analytical stress 

calculation, the deck plate between the two legs of the trough can be modelled as a 

simple clamped beam. The span of this beam is 300 mm, the distance between the 

trough legs. The clamped beam model is only valid for the position exactly at the 

crossbeam. The analytical calculated stresses are significantly higher than the 

measured stresses. This is mainly due to the fact that dispersion of the loads in 

longitudinal direction is not taken into account. 

From the static test became obvious that the width and the length have 

influence on the stress. Wider and longer footprints result in lower stresses at the 

critical locations. This paper has described the static tests very concise. The static 

tests are reported extensively in Stevin Report 6.04.3. (De Jong, 2004-e) 

Fatigue test results, introduction. The fatigue tests are also reported very briefly in 

this paper. For a more extensive description see Stevin report 6.04.4 (De Jong, 2004- 

f). The ranges for test br-08 are in the plastic region. Therefore this test result is 

excluded from the further analysis. 

During the fatigue tests the bridge deck structure is visually inspected on very 

regular basis. Tables 5 and 6 present for test panels A and B, the number of cycles 

and the crack length for the first visual crack observation and for the last observation. 

The number of cycles before the first visual observation is clearly dependent on the 

applied loads. Figures 12 and 13 visualize the crack growth for test panels A and B. 

According to usual definitions in the fracture mechanics the crack depth is defined as 

a (mm) and the total crack length as 2c (mm), however the dimension 2c is defined at 

the top side of the crack, because the observations have been taken place from the top 

side of the bridge deck, see figure 14. It is clearly visible from figures 12 and 13 that 

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the crack growth rate in longitudinal direction, after the crack has been observed at 

the topside of the deck plate, is constant for a total crack length up to 200 mm. This is 

in accordance with previous measurements, (Kolstein, 2000). The load ranges for test 

A are all 64 kN. The load ranges for test B vary from 72 to 75 kN. 

Table 5. Cycles and crack length panel A 

First Visual Crack 

End fatigue test 

Nr. N Length (mm) N Length (mm) 

Trough 1 C 1310910 36 3055450 165 

Trough 1 B 1141172 34 3055450 208 

Trough 2 E 1561051 26 3055450 201 

Trough 2 F 1650740 23 3055450 136 

Trough 3 A 1140605 22 3205000 150 

Trough 3 D 1472200 23 3205000 155 

Table 6. Cycles and crack length panel B 

First Visual Crack 

End fatigue test 

Nr. N Length (mm) N Length (mm) 

Br202 A 875431 5 1036042 40 

Br202 B 479221 10 1036042 120 

Br203 A 679663 12 1119456 92 

Br203 B 1119456 73 1119456 73 

Br204 A 477622 10 779815 85 

Br204 B 477622 10 779815 74 

Br-08 A 166209 25 280345 50 

Br-08 B 280345 15 280345 15 

Br-09 A 539944 30 901153 90 

Br-09 B 869925 8 901153 15 

Br-10 A 667255 10 1010108 75 

Br-10 B 771073 40 1010108 95 

Fatigue test results, crack growth. For both test A and test B a function that 

describes the average crack growth rate is derived from a linear regression analysis. 

These functions are given in the figures 12 and 13. A strong correlation between the 

applied load range and the crack growth rate is obvious from the comparison between 

the crack growth rate in test A and B. For test A d2c/dN = 8.1e-5, for test B d2c/dN = 

2.6e-4. All the data are presented on a log-log scale, and a linear regression analysis 

is executed. This is done to obtain a formula for d2c/dN as a function of ∆σ, where 

∆σ is the stress range in transversal direction at the crack location. This is the 

maximum in line A-A, see figure 9. This formula is: 

d2c 

log = logC 0 − m0 

⋅ log ∆σ 

dN 

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In which: 

m 0 = 2.70 

log C 0 = -10.50 

See figure 15 for a graphical presentation of this analysis. 

Fatigue test results, detail classification. The test data are used to derive 

characteristic fatigue detail classifications. For fatigue design these characteristic 

values should be divided by a factor γ m . The characteristic values are calculated for 

95% survival probability on a two-sided confidence level of 75% of the mean. These 

values are the same as the values on which the detail classifications in Eurocode 3 are 

based. The classification values are at 2e6 cycles. 

To derive a fatigue detail classification it is essential to decide which crack 

length is considered as failure of the deck plate. It is obvious that cracks in the deck 

plate do not threaten the structural integrity when they are short; up to 200 mm. As 

fatigue design calculations are intended to guarantee that no structural failure occurs 

during the service life of a structure, a crack length of 200 mm could possibly be 

defined as crack length at which the fatigue detail classification is chosen. 

The test performed however are ended when the crack length at the top side is 

approximately 100 to 150 mm. Based on the performed tests detail classifications for 

four cracks sizes have been defined. 

1. Crack length top side deck plate = 0 mm 

2. First visual crack = 23 mm (average for test A and B) 



Deriving the detail classification at all four definitions enables the designer in fact to 

calculate crack growth rates in an easy way. 

The number of cycles at 0, 50 and 100 mm crack length is derived from the 

visual observations. Because of the frequent observations during the tests, reliable 

estimations of the numbers of cycles at 0, 50 and 100 mm length have been derived. 

In general this is a dataset of 4 * 18 = 72 points. Some data are removed from the set, 

because they are unreliable, for several reasons. This leads to a reduced data set. 

Based on this reduced dataset the slope m has been derived by a linear regression 

analysis. Statistical evaluation of the data sets for the four cracks sizes has led to the 

detail classifications given in table 7. Figure 16 gives a figure of the analysis. 

In 1998 a detail classification based on fracture mechanics has been derived 

(Dijkstra, 1998). The calculated average value was 156 and the calculated design 

value 115, also according to the Eurocode format. The experimental results are 

somewhat better as the classification based on this crack growth model. 

Table 7. Fatigue classifications 

Crack length (mm) Design value Average value 

0 mm 147 197 

23 mm (average f.v.c) 161 211 

50 mm 173 223 

100 mm 194 251 

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In 1998 some fatigue tests on this detail have been performed (Kolstein, 1999, 

2000). In this tests three cracks, which are grown through the deck plate, have been 

observed. The results of Kolstein fit very well with the results of the tests reported in 

this paper. 

Maintenance Philosophy 

Conventional maintenance strategies for orthotropic steel bridge decks are formed by 

time-based inspections of the bridge structure and the replacement of parts of the 

structure when these parts are at the end of its lifetime. The inspections are intended 

to make decisions about replacement of parts of the structure. The left circle of figure 

17 gives a model of this kind of maintenance. This kind of maintenance is 

appropriate, provided that the time based interval is long and failure of elements 

within this interval doesn’t cause structural failure. 

In case of the fatigue problems on orthotropic steel bridge decks both 

requirements are not met. Experiences on steel bridges in the Netherlands have 

shown that monthly visual inspections on the steel bridge deck structure are necessary 

on the most heavily loaded bridge structures with fatigue cracks. Besides these 

expensive inspections also expensive emergency reparations of the deck structure are 

needed in case severe fatigue cracks are observed. Due to the nature of the fatigue 

phenomenon we can expect that the number of inspections and reparations will 

always increase. The conclusion must be that conventional maintenance is no longer 

appropriate, so the maintenance philosophy has to be changed to a risk based strategy 

(Boersma, 2003, De Jong 2003-a) 

In changing from conventional maintenance to a risk based maintenance 

strategy two major changes can be observed. The time based inspection interval has 

to be replaced by an interval based on a lifetime calculation. Systematic lifetime 

calculations for fatigue cracks are very important for a risk-based strategy. On the 

other hand local (emergency) reparations have to be replaced by renovation of the 

total bridge deck structure. An example of renovation is the replacement of the 

asphalt wearing course by a layer of high performance concrete (De Jong, 2004-d). 

References 

Boersma, P.D, Jong, F.B.P. de (2003), “Techniques & solutions for rehabilitation of 

orthotropic steel bridge decks in the Netherlands”, Conference Proceedings 10 th 

International conference on Structural Faults and Repair on steel structures, London 

Dijkstra, O.D., Vrouwenvelder, A.C.W.M. (1998), “Vermoeiing verkeersbruggen met 

orthotrope dekplaat. Case Brienenoord, TNO-report 98-CON-R0714” (in dutch) 

Eurocode 1991:2-2003 (2003), “Eurocode 1; Basis of design and actions on 

structures; Part 2: Traffic loads on bridges” 

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Groenendijk, J. (1998), “Accelarated testing and surface cracking of asphaltic 

concrete pavements, chapter 4, Diss. Delft University of Technology, Delft 

Jong, F.B.P. de, Kolstein M.H., Bijlaard F.S.K. (2002), “Development of long term 

renovation techniques for orthotropic steel bridge decks with fatigue cracks”, 

Conference Proceedings 3 rd European conference on steel structures, Eurosteel 

2002, vol.2 pp. 769-778, Coimbra 

Jong, F.B.P. de, Boersma, P.D (2003-a), “Lifetime calculations for orthotropic steel 

bridge decks”, Conference Proceedings 10 th International conference on Structural 

Faults and Repair on steel structures, London 

Jong, F.B.P. de (2003-b), “Plan Lintrack reference experiments on conventional 

orthotropic steel bridge decks with surfacings”, Stevin Report 6.03.6 

Jong, F.B.P. de (2003-c), “Data processing & Results Lintrack reference experiments 

on conventional orthotropic steel bridge deck with surfacings”, Stevin Report 6.03.7 

Jong, F.B.P. de (2004-a), “Strain measurement tests at orthotropic steel bridge decks 

with a heavy vehicle simulator, Stresses due to real moving wheel loads in deck plate, 

trough wall and surfacing”, Conference proceedings Nordic Steel Construction 

Conference, Copenhagen, 401-412 

Jong, F.B.P. de (2004-b), “Overview Fatigue phenomenon in orthotropic bridge 

decks in the Netherlands”, Conference proceedings Orthotropic Bridge Conference, 

Sacramento, CA 

Jong, F.B.P. de, Boersma, P.D. (2004-c), “Maintenance philosophy and Systematic 

lifetime assessment for decks suffering from fatigue”, Conference proceedings 

Orthotropic Bridge Conference, Sacramento, CA 

Jong, F.B.P. de, Kolstein, M.H. (2004-d), “Strengthening a bridge deck with high 

performance concrete”, Conference proceedings Orthotropic Bridge Conference, 

Sacramento, CA 

Jong, F.B.P. de (2004-e), “Stress distribution in orthotropic steel bridge decks, 

Measurements and calculations for the crossing trough-crossbeam”, Stevin Report 

6.04.3 

Jong, F.B.P. de (2004-f), “Fatigue tests for deck plate cracks in orthotropic bridge 

decks”, Stevin Report 6.04.4 

Kolstein, M.H., Wardenier, J. (1999), “Laboratory tests of the deckplate weld at the 

intersection of the trough and the crossbeam of steel orthotropic bridge decks”, 

Proceedings of the conference Eurosteel 1999, 411-414 

605 




Kolstein, M.H. (2000), “Laboratory tests orthotropic deck bascule bridge Van 

Brienenoord, Stevin Report 6-98-15 

Leendertz, J.S., Jong F.B.P. de (2003), “Fatigue Aspects of Orthotropic Steel Decks”, 

Conference Proceedings Lightweight Bridge Decks, European Bridge Engineering 

Conference, Paper no. 14, Rotterdam 

Vrouwenvelder, A., Dijkstra, O., Waarts, P., Vervuurt, A. (1998), “Basisfilosofie 

voor het ontwerpen van verkeersbruggen. Onderdeel Vermoeiing van rijdekken”, 

TNO-report 98-CON-R0455 (in dutch) 

Vrouwenvelder, A.C.W.M., Waarts, P.H., Wit, S. de (2000-a), “Algemene 

veiligheidsbeschouwing en modellering van wegverkeersbelasting voor 

brugconstructies”, TNO report 98-CON-R1813 (in dutch) 

Vrouwenvelder, A.C.W.M., Dijkstra, O.D., Foeken, R.J.van (2000-b), “Basisfilosofie 

voor het ontwerpen van verkeersbruggen, Onderdeel: vermoeiing stalen rijdekken, 

Probabilistische ontwerpfilosofie”, TNO report 1999-CON-DYN-R0108 (in dutch) 

606 




Figures 

Fatigue Detail B – Deck plate 

at intersection troughcrossbeam 

(DPS01) 

Surfacing - 

Deck plate 

Crossbeam 

Longitudinal girder (trough) 

Main girder 

Fatigue Detail A – Weld 

trough-deck plate (TRDPL01) 

Fixed bridges: asphalt 

Movable bridges: epoxyresin 

Figure 1. Isometric view of an orthotropic steel bridge deck with 2 fatigue cracks 

Aluminium profile 

Steel deck plate 

Longitudinal girder 

Asphaltic surfacing 

Bituminous interface 

Steel deck plate 

Figure 2. Example of renovation technique 

607 




Figure 3. Test panel Lintrack & Locations strain gauges 

Figure 4. Lintrack apparatus 

608 




Figure 5. Influence surface wheel type B for a strain gauge near location B 

Figure 6. Influence surface wheel type C for a strain gauge near location B 

609 




Figure 7. Test panel A 

Figure 8. Test panel B 

610 




Figure 9. Strain gauges deck plate trough 2 panel A 

611 




Strain over line A-A - test BA1_S8 & Analytical 

1200 

1000 

800 

600 

Strain *e-6 

400 

200 

0 

-250 -200 -150 -100 -50 0 

-200 

50 100 150 200 250 

-400 

-600 

Measurement 

Analytical 

-800 

width (mm) 

Figure 10. Strain over line A-A footprint 8 270 * 320 mm 

Strain over line G-G (left) - test BA1_S8 & analytical 

1200 

1000 

800 

Strain *e-6 

600 

400 

Measurement 

Analytical 

200 

0 

-200 -100 0 100 200 300 400 

length (mm) 

Figure 11. Strain over line G-G footprint 8 270 * 320 mm 

612 




Crack growth (d2c/dN) panel A 

250 

2c (mm) 

200 

150 

100 

50 

A 

B 

C 

D 

E 

F 

Function panel A 

Function panel B 

0 

0 500000 1000000 1500000 2000000 2500000 

N after first visual crack 

Figure 12. Crack growth panel A 

Crack growth (d2c/dN) panel B 

2c (mm) 

140 

120 

100 

80 

60 

40 

20 

0 

br202a 

br202b 

br203a 

br204a 

br204b 

br-09a 

br-09b 

br-10a 

br-10b 

br-08a 

Function panel B 

Function panel A 

0 100000 200000 300000 400000 500000 600000 

N after first visual crack 

Figure 13. Crack growth panel B 

613 




c 

c 

deck plate 

crack 

deck plate 

a 

crack 

trough inside 

trough outside 

trough wall 

crossbeam web 

trough 

wall 

crossbeam 

web 

Figure 14. Definition crack sizes 

log10 d2c/dN 

-3.50 

-3.70 

-3.80 

-3.90 

-4.00 

-4.10 

-4.20 

-4.30 

-4.40 

-4.50 

Crack growth curve 

-3.60 

2.25 2.30 2.35 2.40 2.45 2.50 2.55 2.60 2.65 2.70 2.75 

log10 S 

Measurement 

Analytical model based on 

regression analysis 

Figure 15. Crack growth function 

614 




2.70 

S-N Deck plate cracks - Reduced data 

Log S 

2.60 

2.50 

2.40 

2.30 

2.20 

2.10 

Mean l = 0 mm 

Mean f.v.c. 

Mean l = 50 mm 

Mean l = 100 mm 

Data l = 0 mm 

Data f.v.c. 

Data l = 50 mm 

Data l = 100 mm 

Design l = 0 mm 

Design f.v.c. 



5.00 5.20 5.40 5.60 5.80 6.00 6.20 6.40 

Log N 

Figure 16. Fatigue detail classifications 

(Emergency)reparation 

Inspection 

Inspection 

Lifetime calculation 

A 

Time based interval 

B 

New bridge deck / 

Renovation 

Figure 17. Maintenance philosophy, conventional maintenance (left red circle), 

risk-based maintenance (right green circle) 

615

RESEARCH PROJECT TU DELFT; BEHAVIOUR CONVENTIONAL ...

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