Characterisation and seismic vulnerability assessment of unreinforced masonry buildings in Dunedin CBD
The need for Territorial Authorities (TA) to compile an earthquake-prone building register has been highlighted by the Canterbury Earthquakes Royal Commission and with this in mind the following research was undertaken to enable the characterisation and assessment of potentially earthquake-prone historic unreinforced masonry (URM) buildings in Dunedin. To achieve the research goals, associated technical literature was reviewed and an earthquake-prone building register containing data on 226 URM buildings located in the Dunedin central business district (CBD) area was compiled. Additionally, structural performance of these buildings was also assessed using both the literature suggested initial evaluation procedure and the proposed risk based assessment method. It was estimated that 680 of the existing 750 Dunedin URM buildings are likely to be earthquake-prone and merit detailed assessment. It was also established that the earthquake risk in the city is primarily based on the fact that it has a significant number of URM buildings built prior to the introduction of building code, of which a large proportion is concentrated in the CBD. These not only pose a safety risk to their users but also to pedestrians on the adjacent footpaths.
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