shear capacity of the ruytenschildt bridge
TRANSCRIPT
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
