Shear capacity of the ruytenschildt bridge

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Challenge the future Delft University of Technology Shear capacity of the Ruytenschildt bridge Eva Lantsoght, Cor van der Veen, Ane de Boer

Transcript of Shear capacity of the ruytenschildt bridge

Page 1: Shear capacity of the ruytenschildt bridge

Challenge the future

DelftUniversity ofTechnology

Shear capacity of the Ruytenschildt bridge

Eva Lantsoght, Cor van der Veen, Ane de Boer

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Overview

• Ruytenschildt Bridge testing• Prediction of shear capacity• Comparison test and predictions• Summary & Conclusions

Slab shear experiments, TU Delft

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Ruytenschildt Bridge (1)

• 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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Ruytenschildt Bridge (2)

Existing bridge Partial demolition and building new bridge

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Ruytenschildt Bridge (3)

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Test resultsSpan 1

• Maximum load 3049 kN• Maximum available load for

span 1• Flexural cracks• No failure• Order additional load for

test 2!

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Test resultsSpan 2

• Maximum load 3991 kN• Large flexural cracks• Flexural failure

• yielding of reinforcement• Settlement of bridge pier

with 1.5cm• Elastic recovery to 8mm

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Quick Scan shear capacity (1)

• Method for rating bridges• Spreadsheet for rating all

sections in a span• Changing reinforcement• For EN 1991-2:2003 live loads• Load factors from NEN 8700• Skew factors• Result = Unity Check• Shear stress over shear

capacity

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Quick Scan shear capacity (2)

• Assuming C35/45• Max UC in span 1 = 0.88 close to support 2• Span 1: anchorage insufficient• Max UC in span 2 = 0.78 at x = 1.3 m

• Measured concrete compressive strength• Max UC in span 1: 1.14 close to Support 2• Max UC in span 2: 1.04 at x = 1.3 m

• Shear capacity insufficient at LoA I

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Shear capacity prediction (1)

• Based on average values• To find estimate of maximum load in test• Effective width in shear for skewed slab?• Skewed slab: obtuse corner is governing

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Shear capacity prediction (2)Span Span 1 Span 2Shear capacity

Ptot (kN) Ptot,slab (kN) Ptot (kN) Ptot,slab (kN)

bstr 3760 7606 4020 8132bpara 3236 6546 3432 6943bskew 4804 9718 5328 10779

• Increase in shear capacity measured in slabs: 2.023 (average value)• Based on straight slabs• Valid for skewed slabs?

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Comparison tested and predicted results

• Span 1: no failure• Span 2• Flexural failure• Shear capacity?

• Predictions:• Equal chance of shear and

flexural failure• Ductile vs brittle failure

mode• Shear capacity of skewed

slabs?

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Summary & Conclusions• Ruytenschildt Bridge

• Existing slab bridge scheduled for replacement

• Testing in 2 spans, failure in span 2

• Shear capacity prediction• Quick Scan for rating• Average prediction for test• Effect of skew on shear capacity of

slab and effective width?

• Flexural failure, ductile failure mode