1.
Challenge the future
Delft
University of
Technology
Application of Modified Bond Model
to capacity of Ruytenschildt Bridge
Eva Lantsoght, Cor van der Veen, Ane de Boer, Dick Hordijk

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2
Overview
• Introduction to case
• Modified Bond Model
• Test results
• Comparison results and MBM
• Summary & Conclusions
Slab shear experiments, TU Delft

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Proofloading
Case Ruytenschildt Bridge
• Proofloading to assess capacity of
existing bridge
• ASR affected bridges
• Insufficient information
• Study cracks and deformations for
applied loads
• Crack formation: acoustic emissions
measurements
• Control load process
• Ruytenschildt Bridge: testing to
failure

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Proofloading Ruytenschildt Bridge
Existing bridge Partial demolition and building new bridge

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Proofloading
Case Ruytenschildt Bridge

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Bond Model (1)
• Alexander and Simmonds,
1990
• For slabs with
concentrated load in
middle

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Bond Model (2)

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Modified Bond Model (1)
• Adapted for slabs with concentrated
load close to support
• Geometry is governing as in
experiments
• Determine factor that reduces capacity
of “radial” strip
• Maximum load: based on sum capacity
of 4 strips

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Unequal loading of strips
• Static equilibrium
• v2,x reaches max before v1,x
'
1, 0.1667x c
a
v f d
L a



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Loads close to free edge
Edge effect:
when length of strip is too small to develop loaded length lw

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Cross-sections Ruytenschildt Bridge
• Testing in span 1 and span 2
• close to end support
• close to mid support
• Critical position for shear

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Test results proofloading
Span 1
• Maximum load 3049 kN
• Maximum available load for span 1
• Flexural cracks
• No failure
• Order additional load for test 2!
• Prediction MBM: 2864 kN
• Tested/Predicted = 1.06
• Tested; not failure load
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Load(kN) time (s)

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Test results proofloading
Span 2
• Maximum load 3991 kN
• Large flexural cracks
• Flexural failure
• yielding of reinforcement
• Settlement of bridge pier
with 1.5cm
• Elastic recovery to 8mm
• Prediction MBM: 3816 kN
• Tested/Predicted = 1.05
• Bent-up bars??
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Load(kN) Time(s)

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Conclusions
• Ruytenschildt Bridge
• Testing to failure in 2 spans
• Measurements
• Modified Bond Model
• Plasticity-based model
• For analysis of capacity of slabs
• MBM shows good predictions of capacity
of bridge
• For limited number of field experiments

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Contact:
Eva Lantsoght
E.O.L.Lantsoght@tudelft.nl // elantsoght@usfq.edu.ec
+31(0)152787449