Dr. ir. Eva Lantsoght

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General overview of work/research since graduating from VUB

Current research line: (proof) load testing

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2003-2008: burgerlijk ingenieur bouwkunde

2008-2009: M.S. in structural engineering, Georgia Institute of Technology

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2009-2013: PhD in Civil Engineering

Concrete Structures research group

Promotor: Joost Walraven Co-Promotor: Cor van der Veen

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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

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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

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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

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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)

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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

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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

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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

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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

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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

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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

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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

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Diagnostic load testing Proof load testing

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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

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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 o RC slab bridges

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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?

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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

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Guideline for proof loading of existing bridges for the Netherlands

Flexure + shear

Stop criteria?

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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

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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

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Video

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BELFA Viaduct with ASR-damage Viaduct remained open to

traffic Disturbs AE measurements TU Delft + ifem:

measurements Bridge approved

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System with load spreader beam

Bending moment capacity 1 night closure of bridge TU Delft: measurements Bridge from 1930s Approved with proof load test

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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

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Existing bridge Partial demolition and building new bridge

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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

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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

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Video

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Determination of dimensions Live load: EN 1991-2:2003 RBK load levels

o Different o Different load factors

In FEM model o mx over 3 m o v over 4d

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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

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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

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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)

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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 422

419 422 419

422 519

922 819

722 819

l 0.91% 0.89% 0.96% 0.95% 0.92%

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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)

r 340 r 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.

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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)

r >Pu r >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.

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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

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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

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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

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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

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Contact:

Eva Lantsoght

elantsoght@usfq.edu.ec // E.O.L.Lantsoght@tudelft.nl

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mailto:elantsoght@usfq.edu.ecmailto:E.O.L.Lantsoght@tudelft.nl

Load testing of reinforced concrete bridges in the NetherlandsOverviewBackgroundTU DelftTU Delft: ResearchUniversidad San Francisco de QuitoUniversidad San Francisco de QuitoUniversidad San Francisco de QuitoUniversidad San Francisco de QuitoResearch at TU DelftResearch at TU DelftResearch at TU DelftInternational collaborationAdstrenOverview Load TestingWhy load testing? (1)Why load testing? (2)Types of load testing (1)Types of load testing (2)Stop criteriaProof load testing of bridgesExisting Guidelines for proof loadingExisting Guidelines for proof loadingResearch needTU Delft Proof Load TestsHeidijk & MedemblikMedemblik ifem + BELFAVlijmen-OostHalvemaans BridgeRuytenschildt Bridge (1)Ruytenschildt Bridge (2)Ruytenschildt Bridge (3)Viaduct ZijlwegViaduct de Beek (1)Viaduct De Beek (2)Preparation steps (1)Preparation steps (2)Execution stepsLab testing for analysis (1)Lab testing for analysis (2)Lab Testing for analysis (2)Lab Testing for analysis (3)RecommendationsStop criteria (1)Stop criteria (2)Stop criteria (3)Summary and conclusionsSlide Number 48