Simultaneous effect of slenderness, spatially varying excitation and support flexibility on dynamics of rocking bridges

In conventional bridge design, plastic hinges are permitted at predetermined locations to have controlled damage. However, this damage can cause the loss of bridge functionality and severely disrupt rescue efforts. The subsequent downtime and repair costs can be unpredictable. Recently, an innovative low-damage design has been proposed that allows the footing to be temporarily and partially separated. The first rocking bridge in the world, i.e., the South Rangitikei viaduct, was built in New Zealand and has survived several thousand earthquakes. Studies on rocking bridges have been conducted. However, experimental research is scarce. Most studies have been performed on single bridge segments. Consequently, severe pounding damage to bridges was ignored, although it has been observed in many earthquakes. The first part of this research focuses on single-segment bridges. It enables better interpretations of the result. The effect of slenderness on bridge responses with a rigid support was considered first. The result revealed complex girder-pier-footing interactions. Building upon these results, the subsequent experiments were performed on the bridge-soil system under multi-axial excitations. In the following chapters, poundings between bridge girders and abutments were considered. The effects of support flexibility, slenderness and spatially varying excitations were included to provide a more realistic insight into the bridge behaviour. This research showed that allowing the footing to rock can reduce the maximum pounding force at the girder-girder interface. Poundings can lead to more significant footing settlement and large maximum relative opening displacements between girders. The research confirms the significance of the interrelationship between bridge pier slenderness, support condition and spatial variation of the excitation in the seismic response of rockable bridges.

Name thesis:degree_name

PhD

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Civil Engineering

Grantor dc:publisher

ResearchSpace@Auckland

Year dc:date.issued

2024

Author dc:creator

• Yang, Ziqi

Advisors dc:contributor.advisor

• Chouw, Nawawi
• Larkin, Tam

Statement dc:rights

• Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Licence dc:rights.uri

• https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm

Handle dc:identifier.uri

https://hdl.handle.net/2292/69740

OAI identifier oai:identifier

oai:researchspace.auckland.ac.nz:2292/69740