Paul Bonnet Oxford University paul'bonneteng'ox'ac'uk

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Developing Real TimeSubstructure Dynamic
Testing (RTS testing)

• Paul Bonnet Oxford University
  paul.bonnet_at_eng.ox.ac.uk

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The problemanalyse the behaviour of a structure
in an earthquake
Modelling cracks, fatigue, concrete, strain rate
effects, etc.
Scale effects and/or load capacity cost

• Lets do a
• computer model of
• the structure

Lets build a replica of the structure on a
shaking table
Lets conduct a pseudo-dynamic test on the
structure
Lets conduct a real-time substructure test
All these methods have their inherent
drawbacks
No experimental velocity and inertial effects
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The idea behind RTS testingdivide structure
into a part solved numerically and a part tested
physically.

• 1 numerical substructure
• 1 physical substructure
• 1 emulation interface

affect each other at all times
separate but complementary
have dynamic effects
ensuring correct boundary conditions on each
substructure
For a RTS experiment to work, the 2 substructures
and the interface emulation need to be solved /
tested / conducted SIMULTANEOUSLY in REAL-TIME.
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Examplebehaviour of a dynamically isolated 10
storey building during an earthquake?
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Benefits of RTS testing

• Structural parts of interest gt physically tested
  with the rest offering an infinite repeatability.
• Complete structure is emulated with much lower
  cost capacity than shaking table test.
• Dynamic effects are exact because reproduced in
  real-time.
• gt Practical financial benefits while
  retaining good scientific validity.

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Results of preliminary tests
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Results of preliminary tests
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Challenges / current work

• Quick numerical substructure computation.
• gt Using discrete time integration scheme
  (several schemes to compare).
• Instantaneous actuation is not possible
  (presence of an actuator delay ? instability).
• gt Need to know how much delay, minimise it,
  know how why it varies.
• gt Need to compensate for actuation delay
  (several methods to compare).
• Method needs to be applied proven for
  non-linear numerical physical substructures of
  earthquake engineering size properties.
• gt Conduct a validation test on a 2 storey
  building column.

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If youd like to know more

• come and visit
• us in the Oxford
• University Structural
• Dynamics Laboratory
• paul.bonnet_at_eng.ox.ac.uk Tel [phone]