Dr. Eva Lantsoght provides an overview of her current activities related to load testing research at TU Delft. She discusses (1) her involvement in developing new load testing standards in several countries, (2) conferences where she has presented on the topic, (3) load testing projects she has conducted including beam experiments and full-scale bridge tests, and (4) recommendations for preparing and executing proof load tests on existing bridges.
2. Current activities relatedto load
testing
Overviewof load testing
researchTU Delft
Recommendations
o Preparation of proof load tests
o Execution of proof load tests
Summary and conclusions Slab shear experiments, TU Delft
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3. New load testing standards under development
o Germany
o USA – e-circular load testing bridges (committee chair)
o USA – ACI 437 for buildings (committee member)
o USA – ACI 342 for bridges (broader scope, chapter lead for chapter
load testing)
o Netherlands: further research
o fib – bulletin existingstructures (corresponding author) + towards
new Model Code
Conferences with MS and SS: ACI 2017, IABMAS 2018;
IALCCE 2016 + 2018, BEI 2019, fib 2017…
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5. Presentations from Chancellor Grant 2016 at IALCCE 2018
o Kevin Benitez: Development of a stop criterion for load tests based
on the critical shear displacement theory
o Eva Lantsoght: Proposed stop criteria for proof load testing of
concrete bridges and verification
o Jose Eduardo Paredes: Nonlinear finite element analysis of beam
experiments for stop criteria
o Andres Rodriguez: Verification of flexural stop criteria for proof load
tests on concrete bridges based on beam experiments
Presentation describing current practice in Ecuador at
IALCCE 2018
o Bridge diagnostic load testing in Ecuador – case studies J. Bonifaz,
S. Zaruma, A. Robalino & T.A. Sánchez
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6. September 15th 2020: Deadline for abstract submission
Towards extending the service life of existing concrete
infrastructure through advanced assessment methods
(Special session)
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7. ACI SP-323 (co-editor)
Frontiers Built Environment–
Bridge Engineering article
collection(guest associate
editor)
Two Books: Load Testingof
Bridges (editor) – Structures
and Infrastructuresseries
(2019)
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8. E-circular
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Download link: http://onlinepubs.trb.org/onlinepubs/circulars/ec257.pdf
Primary Contributors:
Sreenivas Alampalli, NYS DOT
Dan M. Frangopol, Lehigh University
Jesse Grimson, BDI
David Kosnik, CTL Group
Marvin Halling, Utah State University
Eva O.L. Lantsoght, USFQ & Delft
Jeff S. Weidner, University of Texas
David Y. Yang, Lehigh University
Y. Edward Zhou, AECOM
Reviewed by:
Erin Bell, University of New Hampshire
Christina Freeman, FL DOT
James Long, PA
Brent Phares, Iowa University
Franklin Moon, Rutgers University
Duane Otter, TTCI
Thomas E. Beitelman, AASHTO T-18 /FL DOT
Stephen Maher, TRB
9. At opening of new
bridge
Reassure traveling
public
Engineer stands under
bridge
Proof load testing
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10. Since 1950s: better
computational
methods
Diagnostic load testing:
SLS
Now: evaluation of
existing structures
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12. Bridges from 60s and 70s
The Hague in 1959
Increasedlive loads
common heavy and long truck (600 kN)
End of service life + larger loads
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15. Diagnostic load testing
Calibration of FEM
Strain gages over girder
height
Low load levels (SLS)
Rating with updated FEM
Or: prior to opening
(presentation Andres R.)
Proof load testing
Directly demonstrate that
bridge fulfils criteria
Higher load levels
Larger involved risk
Follow measurements
Stop criteria
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16. Safety philosophy
Stopcriteria:
o Further loading not permitted
o Failure near
o Irreversible damage near
MSc Thesis W. Vos
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17. Apply predetermined load
to bridge
o Information lacking
o Damage due to ASR, …
Proofload testing
o Immediate approval of
bridge
o Recalculate updated β
o RC slab bridges
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18. DAfStB Richtlinie
Stopcriteria
o Concrete strain
o Steel strain
o Crack width and residual
crack width (new & existing
cracks)
o Residual deflection
For flexure
Structures with large existing
cracking?
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19. North America:
o Buildings: ACI 437.2M-13
o Bridges: Manual of Bridge
Rating Through Load Testing
(1998)
ACI 437.2M-13 stopcriteria:
o Residual deflection
o Permanency ratio
o Deviation from Linearity Index
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21. Proofload tests:
o Heidijk 2007
o Medemblik 2009
o Vlijmen-Oost 2013
o Halvemaans Bridge 2014
o Ruytenschildt Bridge 2014
o Viaduct in the Zijlweg 2015
o Viaduct De Beek 2015
o Vecht Bridge 2016 Load test to failure of Ruytenschildt Bridge, summer 2014
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22. Field inspection
o Dimensions
o Same lay-out as plans?
o Material properties
o Damage maps
o Site restrictions
Prior assessment
o Live load: EN 1991-2:2003
o RBK load levels
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23. Critical position
o Bending moment: largest
moment
o Shear: 2.5d from support
Requiredproof load
o Same shear or bending
moment as with load
combination
o Value → considered safety
level
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24. Cyclic loading scheme
o Acoustic emission measurements
o Check linearity and reproducibility of measurements
o Check residual deformations
Stopcriteria
o Evaluated during tests
o Research in progress
o Criteria for shear failure need to be developed
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26. Beamsfrom Ruytenschildt Bridge
o Cyclic loading protocol
o Tests: Failure in shear and flexure
Beamscast in lab
o plain reinforcement
o cyclic loading
o shear and flexural failure
Beams RSB01 after failure (Yang, 2015)
Yang, Y. (2015)."Experimental Studieson theStructural Behavioursof Beamsfrom RuytenschildtBridge,"
Stevin Report 25.5-15-09,Delft Universityof Technology, Delft, 76 pp.
Beams RSB02B after failure (Yang, 2015)
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27. Load testing:internationalinterest
History:prior to opening
Now: existingbridges
Best practices
o Identify goals
o Preparation
o Inspection
o Monitoring
o Cyclic loading
Viaduct Zijlweg, tested in summer 2015
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28. (Former) colleagues at TU Delft: Albert Bosman, Sebastiaan
Ensink, Dick Hordijk, Rutger Koekkoek, Marco Roosen, Cor
van der Veen, Patrick van Hemert, Yuguang Yang
Students at TU Delft: Arthur Ennoudi, Thomas Harrewijn, Rik
Tersteeg, Werner Vos
Rijkswaterstaat: Ane de Boer, Sonja Fennis, Marius
Naaktgeboren, Herbert van der Ham
Contractors: de Boer en de Groot, Witteveen+Bos (Frank
Linthorst, Danny den Boef)
Load execution: Mammoet: Otto Illing, Chris Huissen
Funding: Noord Holland, Friesland, Rijkswaterstaat,
Chancellor Grants USFQ
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