Seismic design of South Brighton bridge
A decision against mechanical energy dissipators
DOI:
https://doi.org/10.5459/bnzsee.11.2.110-120Abstract
The seismic design of a proposed Christchurch bridge is discussed. Initial design was based on supporting the superstructure on elastomeric bearing pads and steel-cantilever dampers. Dynamic analyses showed that the dampers were relatively ineffective, and that the seismic response was dictated by the characteristics of the bearing pads. Final design, based on a conventional ductile approach was found to be more economical without significant increase to seismic risk. It is shown that the decision to opt for a design incorporating mechanical energy dissipators as opposed to a monolithic pier/superstructure design will not necessarily result in a reduction in seismic response.
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