 
Dr. ir. Eva Lantsoght
10/28/2016
1
 General overview of
work/research since
graduating from VUB
 Current research line:
(proof) load testing
10/28/2016 2
 2003-2008: burgerlijk
ingenieur bouwkunde
 2008-2009: M.S. in structural
engineering, Georgia Institute
of Technology
10/28/2016 3
 2009-2013: PhD in Civil
Engineering
 Concrete Structures research
group
 Promotor: Joost Walraven
 Co-Promotor: Cor van der Veen
10/28/2016 4
 Experiments
o Shear in reinforced concrete slabs
o 156 experiments
 Analytical work
o Extended Strip Model – plastic
analysis method for shear in slabs
o Probability-based improvement for EC
shear formula based on experiments
 Practical application
o Quick Scan for Rijkswaterstaat
10/28/2016 5
 2013 – …
 B.Sc. level, 5-year program
 Teaching (3 courses/semester):
o Reinforced Concrete I
o Reinforced Concrete II
o Construction Materials Lab
o Design of Pavements
o Structural Analysis I
 Research with students for
“Trabajo de Titulacion”
10/28/2016 6
 2013-2016: Profesor auxiliar
 2016 (?) - … : Profesor
Investigador Principal Titular
after concurso de
merecimientos y oposiciones
=> reduction of teaching,
more research
 ACI student chapter
 ASCE student chapter
 2013 – 2016: Starting ICV-Lab
10/28/2016 7
 Research:
o Publications of PhD research
o Analysis existing bridge Tambura
o Torsion in slabs
o Digital Image Correlation with
cheap tools
o Chancellor Grant 2015: Extended
Strip Model
o Chancellor Grant 2016: Stop
criteria load testing (research line
TU Delft)
10/28/2016 8
 Research lines:
o Difficulties:
• contact with Ministry of Public Works?
• Infomation (structural plans?)
• Mentality: no interest in existing structures
• Limited facilities
• No research group
o Approach:
• Desk research
• Presentations about existing structures and
maintenance
• Cooperation through international committees
10/28/2016 9
 2013 – now: 0,2 fte
 Short projects
 Summer 2013:
o Quick Scan spreadsheets for
Rijkswaterstaat
 Summer 2014:
o Fatigue of high-strenght concrete:
proposal for Dutch code
o Ruytenschildt Bridge collapse test
10/28/2016 10
 Summer 2015:
o Effect of ASR on shear- and
bending moment capacity
o Proof load test viaduct Zijlweg
o Support for research line proof
load testing
10/28/2016 11
 Summer 2016
o Research line proof load testing
o Beam tests + analysis of results
o Analysis results of proof load test
viaduct De Beek
o Literature review
o Overview previous proof load tests
in NL
o First draft guideline
o Vechtbrug: last week – collapse
test
10/28/2016 12
 ACI-ASCE 421: Design of reinforced concrete slabs
 ACI-ASCE 445: Shear & Torsion
 ACI-DAfStB 445-D: Shear Databases
 ACI 342: Evaluation of Concrete Bridges and Bridge
Elements
 TRB AFF30: Concrete Bridges
 TRB AFF40: Testing and Evaluation of Transportation
Structures
 IABMAS, IALCCE, IABSE, fib
10/28/2016 13
 Advanced structural
engineering
 2 junior engineers
 Bridges: La Armenia, Los
Pajaros (ILM), Villorita
 Buildings
 Project on concrete masonry
houses (EQ-resistant) for
coast of Ecuador
10/28/2016 14
 Introduction
o Why proof loading?
o Stop criteria?
 Overview of existing guidelines
 Past proof load tests by TU Delft
 Recommendations
o Preparation of proof load tests
o Execution of proof load tests
 Summary and conclusions
Slab shear experiments, TU Delft
10/28/2016 15
Bridges from 60s and 70s
The Hague in 1959
Increased live loads
common heavy and long truck (600 kN)
End of service life + larger loads
10/28/2016 16
10/28/2016 17
Diagnostic load testing Proof load testing
10/28/2016 18
Barcza ridge, Poland (Olaszek et
al., 2012)
Delaware (Jones, 2011)
Diagnostic load testing
 Calibration of FEM
 Strain gages over girder
height
 Low load levels
 Rating with updated FEM
Proof load testing
 Directly demonstrate that
bridge fulfils criteria
 Higher load levels
 Larger involved risk
 Follow measurements
 Stop criteria
10/28/2016 19
 Safety philosophy
 Stop criteria:
o Further loading not permitted
o Failure near
o Irreversible damage near
MSc Thesis W. Vos
10/28/2016 20
 Apply predetermined load
to bridge
o Information lacking
o Damage due to ASR, …
 Proof load testing
o Immediate approval of
bridge
o Recalculate updated β
o RC slab bridges
10/28/2016 21
 Europe: DAfStB Richtlinie
 Stop criteria
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?
10/28/2016 22
 North America:
o Buildings: ACI 437.2M-13
o Bridges: Manual of Bridge
Rating Through Load Testing
(1998)
 ACI 437.2M-13 stop criteria:
o Residual deflection
o Permanency ratio
o Deviation from Linearity Index
10/28/2016 23
 Guideline for proof loading of existing bridges for the
Netherlands
 Flexure + shear
 Stop criteria?
10/28/2016 24
 Proof load 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
10/28/2016 25
 Heidijk
o RC slab bridge
o ASR-induced damage
o Loading frame
o RWS + TNO
 Medemblik
o Girder bridge
o BELFA
o RWS + TNO + ifem
10/28/2016 26
 Video
10/28/2016 27
 BELFA
 Viaduct with ASR-damage
 Viaduct remained open to
traffic
 Disturbs AE measurements
 TU Delft + ifem:
measurements
 Bridge approved
10/28/2016 28
 System with load spreader
beam
 Bending moment capacity
 1 night closure of bridge
 TU Delft: measurements
 Bridge from 1930s
 Approved with proof load test
10/28/2016 29
 Existing reinforced concrete slab
bridge (1962)
 Test to failure in two spans
 4 concentrated load – one tandem
 Cyclic loading protocol
 Failure only achieved in span 2
10/28/2016 30
Existing bridge Partial demolition and building new bridge
10/28/2016 31
10/28/2016 32
 Proof load test for bending
moment and shear
 Bridge closed for 1 week
 Viaduct over highway
 ASR-induced damage
 Approved thanks to proof
load test
10/28/2016 33
 No material damage
 Extensive cracking
 Proof load test on Span 1
 Span 2 over highway
 Shear and flexure position
 Bridge approved if 7% plastic
redistribution in Span 2 is OK
 Check for durability/corrosion
10/28/2016 34
 Video
10/28/2016 35
 Determination of dimensions
 Live load: EN 1991-2:2003
 RBK load levels
o Different β
o Different load factors
 In FEM model
o mx over 3 m
o v over 4d
10/28/2016 36
 Critical position
o Bending moment: largest
moment
o Shear: 2.5d from Support
 Required proof load
o Same shear or bending
moment as with load
combination
o Value → considered safety
level
10/28/2016 37
 Cyclic loading scheme
o Acoustic emission measurements
o Check linearity and reproducibility of measurements
o Check residual deformations
 Stop criteria
o Evaluated during tests
o Research in progress
o Criteria for shear failure need to be developed
10/28/2016 38
 Beams from Ruytenschildt Bridge
o Cyclic loading protocol
o Tests: Failure in shear and flexure
o Measurements:
• Lasers: deflection of beam
• LVDTs: crack opening
• Acoustic emission sensors
Beams RSB01 after failure (Yang, 2015)
Yang, Y. (2015). "Experimental Studies on the Structural Behaviours of Beams from Ruytenschildt Bridge,"
Stevin Report 25.5-15-09, Delft University of Technology, Delft, 76 pp.
Beams RSB02B after failure (Yang, 2015)
10/28/2016 39
RSB 01F 02A 02B 03F 03A
d (mm) 503 515.5 520 521 515
Ac (m2) 0.290 0.297 0.307 0.596 0.537
Rebar 4Ø22
4Ø19
4Ø22
4Ø19
4Ø22
5Ø19
9Ø22
8Ø19
7Ø22
8Ø19
ρl 0.91% 0.89% 0.96% 0.95% 0.92%
10/28/2016 40
 Analysis of stop criteria ACI 437.2M-13 and DAfStB
Richtlinie for RSB03F – Flexure test
ACI 437.2M-13
Criterion
Load (kN) DAfStB
Criterion
Load (kN)
Δr 340 Δr 150
Ipr >Pu w new crack 300
IDL 250 Strain -
PACI,st 250 PDA,st 150
Pu 606.6 Pu 606.6
PACI,st/Pu 0.41 PDA,st/Pu 0.25
Tersteeg, R. H. D. (2015). "Proefbelastingen op betonnen bruggen," B.Sc. Thesis,
Delft University of Technology, Delft, The Netherlands, pp. 69.
10/28/2016 41
 Analysis of stop criteria ACI 437.2M-13 and DAfStB
Richtlinie for RSB03A – Shear test
ACI 437.2M-13
Criterion
Load (kN) DAfStB
Criterion
Load (kN)
Δr >Pu Δr >Pu
Ipr >Pu w new crack 690
IDL 390 Strain -
PACI,st 390 PDA,st 690
Pu 706.7 Pu 706.7
PACI,st/Pu 0.55 PDA,st/Pu 0.98
Tersteeg, R. H. D. (2015). "Proefbelastingen op betonnen bruggen," B.Sc. Thesis,
Delft University of Technology, Delft, The Netherlands, pp. 69.
10/28/2016 42
 Use cyclic load protocol
o Study linearity and repeatability of results
 Flexure: Stop criteria exceeded long before failure
o Suitable stop criteria
• Crack width criterion from DAfStB + add lower bound
• Residual deflection DAfStB / ACI 437.2M-13 + minimum load level
• Deviation from Linearity ACI 437.2M-13: consistent performance except for
retested beam
• BUT: Deviation from Linearity and Permanency Ratio depend on applied loading
protocol
 Shear:
o Need to develop stop criteria
o Research on acoustic emission measurements
10/28/2016 43
 Controlled experiments in
laboratory
 Heavily instrumented beams
 Beams: part of series of
shear tests
 Study of stop criteria and
loading protocol
o Interrelated!
 First proposal for stop criteria
for guideline
10/28/2016 44
Previously cracked in bending moment or not?
Failure mechanism Uncracked Cracked
Flexural failure Concrete strains
wmax ≤ 0.5 mm
wres ≤ 0.1 mm
Stiffness reduction ≤ 25
%
Deformation profiles
Load-displacement graph
Concrete strains
wmax ≤ 0.5 mm
wres ≤ 0.1 mm
Stiffness reduction ≤ 5 %
Deformation profiles
Load-displacement graph
Shear failure Concrete strains
wmax ≤ 0.3 mm
Stiffness reduction ≤ 5 %
Deformation profiles
Load-displacement graph
Concrete strains
Stiffness reduction ≤ 5 %
Deformation profiles
Load-displacement graph
10/28/2016 45
10/28/2016 46
 Proof loading to approve existing
bridges
 Existing guidelines:
o Only flexure
o Cracked structures?
 Research on stop criteria
 Determination of maximum proof
load
o LFEA
o Different safety levels
 Execution
o Cyclic loading protocol
o Safely applying large loads
Viaduct Zijlweg, tested in summer 2015
10/28/2016 47
Contact:
Eva Lantsoght
elantsoght@usfq.edu.ec // E.O.L.Lantsoght@tudelft.nl
10/28/2016 48

Load testing of reinforced concrete bridges in the Netherlands

  • 1.
      Dr. ir.Eva Lantsoght 10/28/2016 1
  • 2.
     General overviewof work/research since graduating from VUB  Current research line: (proof) load testing 10/28/2016 2
  • 3.
     2003-2008: burgerlijk ingenieurbouwkunde  2008-2009: M.S. in structural engineering, Georgia Institute of Technology 10/28/2016 3
  • 4.
     2009-2013: PhDin Civil Engineering  Concrete Structures research group  Promotor: Joost Walraven  Co-Promotor: Cor van der Veen 10/28/2016 4
  • 5.
     Experiments o Shearin reinforced concrete slabs o 156 experiments  Analytical work o Extended Strip Model – plastic analysis method for shear in slabs o Probability-based improvement for EC shear formula based on experiments  Practical application o Quick Scan for Rijkswaterstaat 10/28/2016 5
  • 6.
     2013 –…  B.Sc. level, 5-year program  Teaching (3 courses/semester): o Reinforced Concrete I o Reinforced Concrete II o Construction Materials Lab o Design of Pavements o Structural Analysis I  Research with students for “Trabajo de Titulacion” 10/28/2016 6
  • 7.
     2013-2016: Profesorauxiliar  2016 (?) - … : Profesor Investigador Principal Titular after concurso de merecimientos y oposiciones => reduction of teaching, more research  ACI student chapter  ASCE student chapter  2013 – 2016: Starting ICV-Lab 10/28/2016 7
  • 8.
     Research: o Publicationsof PhD research o Analysis existing bridge Tambura o Torsion in slabs o Digital Image Correlation with cheap tools o Chancellor Grant 2015: Extended Strip Model o Chancellor Grant 2016: Stop criteria load testing (research line TU Delft) 10/28/2016 8
  • 9.
     Research lines: oDifficulties: • contact with Ministry of Public Works? • Infomation (structural plans?) • Mentality: no interest in existing structures • Limited facilities • No research group o Approach: • Desk research • Presentations about existing structures and maintenance • Cooperation through international committees 10/28/2016 9
  • 10.
     2013 –now: 0,2 fte  Short projects  Summer 2013: o Quick Scan spreadsheets for Rijkswaterstaat  Summer 2014: o Fatigue of high-strenght concrete: proposal for Dutch code o Ruytenschildt Bridge collapse test 10/28/2016 10
  • 11.
     Summer 2015: oEffect of ASR on shear- and bending moment capacity o Proof load test viaduct Zijlweg o Support for research line proof load testing 10/28/2016 11
  • 12.
     Summer 2016 oResearch line proof load testing o Beam tests + analysis of results o Analysis results of proof load test viaduct De Beek o Literature review o Overview previous proof load tests in NL o First draft guideline o Vechtbrug: last week – collapse test 10/28/2016 12
  • 13.
     ACI-ASCE 421:Design of reinforced concrete slabs  ACI-ASCE 445: Shear & Torsion  ACI-DAfStB 445-D: Shear Databases  ACI 342: Evaluation of Concrete Bridges and Bridge Elements  TRB AFF30: Concrete Bridges  TRB AFF40: Testing and Evaluation of Transportation Structures  IABMAS, IALCCE, IABSE, fib 10/28/2016 13
  • 14.
     Advanced structural engineering 2 junior engineers  Bridges: La Armenia, Los Pajaros (ILM), Villorita  Buildings  Project on concrete masonry houses (EQ-resistant) for coast of Ecuador 10/28/2016 14
  • 15.
     Introduction o Whyproof loading? o Stop criteria?  Overview of existing guidelines  Past proof load tests by TU Delft  Recommendations o Preparation of proof load tests o Execution of proof load tests  Summary and conclusions Slab shear experiments, TU Delft 10/28/2016 15
  • 16.
    Bridges from 60sand 70s The Hague in 1959 Increased live loads common heavy and long truck (600 kN) End of service life + larger loads 10/28/2016 16
  • 17.
  • 18.
    Diagnostic load testingProof load testing 10/28/2016 18 Barcza ridge, Poland (Olaszek et al., 2012) Delaware (Jones, 2011)
  • 19.
    Diagnostic load testing Calibration of FEM  Strain gages over girder height  Low load levels  Rating with updated FEM Proof load testing  Directly demonstrate that bridge fulfils criteria  Higher load levels  Larger involved risk  Follow measurements  Stop criteria 10/28/2016 19
  • 20.
     Safety philosophy Stop criteria: o Further loading not permitted o Failure near o Irreversible damage near MSc Thesis W. Vos 10/28/2016 20
  • 21.
     Apply predeterminedload to bridge o Information lacking o Damage due to ASR, …  Proof load testing o Immediate approval of bridge o Recalculate updated β o RC slab bridges 10/28/2016 21
  • 22.
     Europe: DAfStBRichtlinie  Stop criteria 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? 10/28/2016 22
  • 23.
     North America: oBuildings: ACI 437.2M-13 o Bridges: Manual of Bridge Rating Through Load Testing (1998)  ACI 437.2M-13 stop criteria: o Residual deflection o Permanency ratio o Deviation from Linearity Index 10/28/2016 23
  • 24.
     Guideline forproof loading of existing bridges for the Netherlands  Flexure + shear  Stop criteria? 10/28/2016 24
  • 25.
     Proof loadtests: 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 10/28/2016 25
  • 26.
     Heidijk o RCslab bridge o ASR-induced damage o Loading frame o RWS + TNO  Medemblik o Girder bridge o BELFA o RWS + TNO + ifem 10/28/2016 26
  • 27.
  • 28.
     BELFA  Viaductwith ASR-damage  Viaduct remained open to traffic  Disturbs AE measurements  TU Delft + ifem: measurements  Bridge approved 10/28/2016 28
  • 29.
     System withload spreader beam  Bending moment capacity  1 night closure of bridge  TU Delft: measurements  Bridge from 1930s  Approved with proof load test 10/28/2016 29
  • 30.
     Existing reinforcedconcrete slab bridge (1962)  Test to failure in two spans  4 concentrated load – one tandem  Cyclic loading protocol  Failure only achieved in span 2 10/28/2016 30
  • 31.
    Existing bridge Partialdemolition and building new bridge 10/28/2016 31
  • 32.
  • 33.
     Proof loadtest for bending moment and shear  Bridge closed for 1 week  Viaduct over highway  ASR-induced damage  Approved thanks to proof load test 10/28/2016 33
  • 34.
     No materialdamage  Extensive cracking  Proof load test on Span 1  Span 2 over highway  Shear and flexure position  Bridge approved if 7% plastic redistribution in Span 2 is OK  Check for durability/corrosion 10/28/2016 34
  • 35.
  • 36.
     Determination ofdimensions  Live load: EN 1991-2:2003  RBK load levels o Different β o Different load factors  In FEM model o mx over 3 m o v over 4d 10/28/2016 36
  • 37.
     Critical position oBending moment: largest moment o Shear: 2.5d from Support  Required proof load o Same shear or bending moment as with load combination o Value → considered safety level 10/28/2016 37
  • 38.
     Cyclic loadingscheme o Acoustic emission measurements o Check linearity and reproducibility of measurements o Check residual deformations  Stop criteria o Evaluated during tests o Research in progress o Criteria for shear failure need to be developed 10/28/2016 38
  • 39.
     Beams fromRuytenschildt Bridge o Cyclic loading protocol o Tests: Failure in shear and flexure o Measurements: • Lasers: deflection of beam • LVDTs: crack opening • Acoustic emission sensors Beams RSB01 after failure (Yang, 2015) Yang, Y. (2015). "Experimental Studies on the Structural Behaviours of Beams from Ruytenschildt Bridge," Stevin Report 25.5-15-09, Delft University of Technology, Delft, 76 pp. Beams RSB02B after failure (Yang, 2015) 10/28/2016 39
  • 40.
    RSB 01F 02A02B 03F 03A d (mm) 503 515.5 520 521 515 Ac (m2) 0.290 0.297 0.307 0.596 0.537 Rebar 4Ø22 4Ø19 4Ø22 4Ø19 4Ø22 5Ø19 9Ø22 8Ø19 7Ø22 8Ø19 ρl 0.91% 0.89% 0.96% 0.95% 0.92% 10/28/2016 40
  • 41.
     Analysis ofstop criteria ACI 437.2M-13 and DAfStB Richtlinie for RSB03F – Flexure test ACI 437.2M-13 Criterion Load (kN) DAfStB Criterion Load (kN) Δr 340 Δr 150 Ipr >Pu w new crack 300 IDL 250 Strain - PACI,st 250 PDA,st 150 Pu 606.6 Pu 606.6 PACI,st/Pu 0.41 PDA,st/Pu 0.25 Tersteeg, R. H. D. (2015). "Proefbelastingen op betonnen bruggen," B.Sc. Thesis, Delft University of Technology, Delft, The Netherlands, pp. 69. 10/28/2016 41
  • 42.
     Analysis ofstop criteria ACI 437.2M-13 and DAfStB Richtlinie for RSB03A – Shear test ACI 437.2M-13 Criterion Load (kN) DAfStB Criterion Load (kN) Δr >Pu Δr >Pu Ipr >Pu w new crack 690 IDL 390 Strain - PACI,st 390 PDA,st 690 Pu 706.7 Pu 706.7 PACI,st/Pu 0.55 PDA,st/Pu 0.98 Tersteeg, R. H. D. (2015). "Proefbelastingen op betonnen bruggen," B.Sc. Thesis, Delft University of Technology, Delft, The Netherlands, pp. 69. 10/28/2016 42
  • 43.
     Use cyclicload protocol o Study linearity and repeatability of results  Flexure: Stop criteria exceeded long before failure o Suitable stop criteria • Crack width criterion from DAfStB + add lower bound • Residual deflection DAfStB / ACI 437.2M-13 + minimum load level • Deviation from Linearity ACI 437.2M-13: consistent performance except for retested beam • BUT: Deviation from Linearity and Permanency Ratio depend on applied loading protocol  Shear: o Need to develop stop criteria o Research on acoustic emission measurements 10/28/2016 43
  • 44.
     Controlled experimentsin laboratory  Heavily instrumented beams  Beams: part of series of shear tests  Study of stop criteria and loading protocol o Interrelated!  First proposal for stop criteria for guideline 10/28/2016 44
  • 45.
    Previously cracked inbending moment or not? Failure mechanism Uncracked Cracked Flexural failure Concrete strains wmax ≤ 0.5 mm wres ≤ 0.1 mm Stiffness reduction ≤ 25 % Deformation profiles Load-displacement graph Concrete strains wmax ≤ 0.5 mm wres ≤ 0.1 mm Stiffness reduction ≤ 5 % Deformation profiles Load-displacement graph Shear failure Concrete strains wmax ≤ 0.3 mm Stiffness reduction ≤ 5 % Deformation profiles Load-displacement graph Concrete strains Stiffness reduction ≤ 5 % Deformation profiles Load-displacement graph 10/28/2016 45
  • 46.
  • 47.
     Proof loadingto approve existing bridges  Existing guidelines: o Only flexure o Cracked structures?  Research on stop criteria  Determination of maximum proof load o LFEA o Different safety levels  Execution o Cyclic loading protocol o Safely applying large loads Viaduct Zijlweg, tested in summer 2015 10/28/2016 47
  • 48.
    Contact: Eva Lantsoght elantsoght@usfq.edu.ec //E.O.L.Lantsoght@tudelft.nl 10/28/2016 48