This document discusses proof loading tests that were conducted on existing reinforced concrete bridges in the Netherlands. It provides details on 4 case studies where bridges were loaded to determine their load capacity. Sensors like lasers, acoustic emissions equipment and LVDTs were used to monitor the bridges' response. The results showed that hydraulic jacks were better than other methods for applying concentrated loads. Determining the maximum load and developing appropriate stop criteria for bending and shear are areas of ongoing research to establish guidelines for proof loading existing bridges in the Netherlands.

1. Challenge the future
Delft
University of
Technology
Proof loading
of existing reinforced concrete bridges in The Netherlands
Eva Lantsoght, Dick Hordijk, Cor van der Veen, Ane de Boer

2. 2Proof loading of existing reinforced concrete bridges in The Netherlands
Proof loading of bridges
• Apply predetermined load to
bridge
• Information lacking
• Damage due to ASR, …
• But: probabilistic analysis
• Maximum load?
• Deterministic in load test
• Variable live load in reality
• “Stop criteria”?

3. 3Proof loading of existing reinforced concrete bridges in The Netherlands
Current codes for proof loading
• Europe: DAfStB Richtlinie
• North America:
• Buildings: ACI 437.2M-13
• Bridges: Manual of Bridge
Rating Through Load
Testing (1998)
• But: stop criteria for cracked
structures?

4. 4Proof loading of existing reinforced concrete bridges in The Netherlands
Research need
• Guideline for proof loading of existing bridges for The
Netherlands
• Flexure + shear
• Stop criteria? Different for flexure + shear!

5. 5Proof loading of existing reinforced concrete bridges in The Netherlands
Methods
• Proof load tests:
• Vlijmen-Oost
• Halvemaans Bridge,
Alkmaar
• Ruytenschildt Bridge
• Viaduct in the Zijlweg

6. 6Proof loading of existing reinforced concrete bridges in The Netherlands
Vlijmen-Oost
• Loading: BELFA
• Viaduct with ASR
• Testing while viaduct was in
service
• Measurements:
• Lasers
• Acoustic emissions
• LVDTs

7. 7Proof loading of existing reinforced concrete bridges in The Netherlands
Halvemaans Bridge Alkmaar
• Load application: counter weight
• Flexural capacity
• Bridge closed for 1 night
• Measurements:
• Lasers
• Acoustic emissions
• LVDTs

8. 8Proof loading of existing reinforced concrete bridges in The Netherlands
Ruytenschildt Bridge (1)
• Load application: counter weight
• Measurements:
• Lasers
• Acoustic emissions (2 teams)
• LVDTs
• Sawcut for testing
• Testing to failure
• More details today 1pm:
• Recent Developments in Two-way Slabs:
Design, Analysis, Construction, and
Evaluation

9. 9Proof loading of existing reinforced concrete bridges in The Netherlands
Ruytenschildt Bridge (2)
• Study cracks and deformations for applied loads
• Crack formation: acoustic emissions measurements
• Control load process

10. 10Proof loading of existing reinforced concrete bridges in The Netherlands
Viaduct in the Zijlweg
• Loading: counter weight
• Viaduct with ASR
• Viaduct closed for 1 week
• Measurements:
• Lasers
• Acoustic emissions
• LVDTs

11. 11Proof loading of existing reinforced concrete bridges in The Netherlands
Results of proof load tests (1)
• Load application method:
• Hydaulic jacks: allows higher
load on wheel prints
• BELFA: limited to total load of
90 metric tons

12. 12Proof loading of existing reinforced concrete bridges in The Netherlands
Results of proof load tests (2)
• Determination of maximum
load in test:
• Moment due to applied load
• = moment due to Eurocode
loads
• Find critical location
• Same procedure for shear
• Use LFEA

13. 13Proof loading of existing reinforced concrete bridges in The Netherlands
Results of proof load tests (3)
• Different reliability levels
• As prescribed by NEN 8700:2011
• Different requirements for structure
• Different partial load factors
Case β Ptot (kN) Ptot
(metric ton)
EC 4,3 (?) 1259 128
RBK Design 4,3 1257 128
RBK Reconstuction + 5% 1146 117
RBK Reconstruction 3,6-3,8 1091 111
RBK Usage 3,3 1050 107
RBK Disapproval 3,1 1049 107
SLS ? 815 83

14. 14Proof loading of existing reinforced concrete bridges in The Netherlands
Results of proof load tests (4)
0
20
40
60
80
100
120
0 50 100 150
Appliedtotalload
[tonnes]
Time [min]
Loading procedure SLS Reconstruction Reconstruction + 5%

15. 15Proof loading of existing reinforced concrete bridges in The Netherlands
Results of proof load tests (5)
• Measurements: experience
• Development of aluminum
frame
• Research on Acoustic
Emissions
• Necessary for stop criteria
• Load cells at jacks
LVDT
Laser distance
finder

16. 16Proof loading of existing reinforced concrete bridges in The Netherlands
Summary and conclusions
• Research in The Netherlands
• Executed load tests
• Loading with hydraulic jacks
• Measurement and
interpretation
• Current work:
• Determination of maximum
load
• Stop criteria for bending and
shear

17. 17Proof loading of existing reinforced concrete bridges in The Netherlands
Contact:
Eva Lantsoght
E.O.L.Lantsoght@tudelft.nl // elantsoght@usfq.edu.ec
+31(0)152787449