Damage identification of unreinforced masonry structures based on vibration response

This thesis presents the findings of an investigation on the dynamic characterization of unreinforced masonry (URM) buildings and the use of their distinctive modal properties in identifying damage. Numerical and physical models were used to analyse the applicability of system and damage identification techniques to non-slender URM buildings. Modal tests were conducted on two undamaged URM panels and an undamaged model of a one-storey URM house. Impacts with a calibrated hammer were used to excite the specimens during the modal test, and also horizontal harmonic excitations in the case of the house model. Two system identification techniques (SSI and FDD) were considered for extracting the modal properties. The experimental results were then compared with numerical predictions obtained from finite element models, originally generated based on geometrical and mechanical properties obtained by standardized tests. The numerical predictions were improved by applying sensitivity-based model updating techniques. The evolution of the modal properties of the URM panels and house model due to damage artificially induced were also investigated. Vibration-based and model updating-based damage identification techniques were employed to detect the damage distribution in the specimens. Finally, a seismic assessment was conducted on a typical New Zealand URM building by applying time-history analysis on finite element models. An original seismic hazard zonation and methodology for selecting appropriate ground-motion records in the North Island of New Zealand is described. A typical stand-alone two-storey URM building was simulated using different finite element models. Material and geometrical properties estimated from traditional standardized test results, and properties estimated by a process of model updating based on the experimental data recorded in the vibration tests were considered for these models. The finite element models were analysed using a time-history methodology for a building in Auckland and Wellington. The response of the building was compared with admissible limits established based on a stability criteria, taking into account three levels of intensity for the ground motion.

Name thesis:degree_name

PhD

Level thesis:degree_level

Doctoral

Grantor dc:publisher

ResearchSpace@Auckland

Year dc:date.issued

2012

Author dc:creator

• Oyarzo Vera, Claudio

Advisors dc:contributor.advisor

• Chouw, N
• Ingham, J

Statement dc:rights

• Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher.

Licence dc:rights.uri

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

Handle dc:identifier.uri

https://hdl.handle.net/2292/19371

OAI identifier oai:identifier

oai:researchspace.auckland.ac.nz:2292/19371