Seismic rehabilitation of existing concrete and masonry buildings

包括维多利亚、温哥华和蒙特利尔在内的加拿大几个大都会地区过去都经历过地震，未来肯定会发生地震。这些地区的基础设施老化和人口密度增加，导致建筑物、桥梁和公用事业在发生大地震时遭受重大破坏的风险增加。加利福尼亚州和日本最近发生的地震表明，在20世纪70年代中期S时期之前建造的混凝土和砖石建筑特别容易受到严重的结构破坏，甚至倒塌。但并不是所有的混凝土和砖石建筑都会对生命安全构成威胁，建筑所有者对改造大量现有建筑的高昂成本感到沮丧，而工程师们则难以确定未来地震中可能倒塌的真正脆弱的建筑。需要进行研究，以帮助工程师和建筑物业主面对通过地震修复减少我们城市中心现有结构的地震风险这一具有挑战性的任务。拟议的研究将努力消除混凝土和砖石建筑在地震修复方面面临的障碍，从而最大限度地减少加拿大人面临的地震风险。特别是，这项研究将侧重于三个主题，旨在帮助更好地了解现有建筑物的抗震性能，从而能够设计具有成本效益的翻新战略：(1)强度退化对位移需求的影响；(2)无筋砌体墙的平面外反应对面内剪切损伤的敏感性；以及(3)材料劣化对现有建筑物抗震性能的影响。

Several metropolitan regions in Canada, including Victoria, Vancouver, and Montreal, have experienced earthquakes in the past, and will most certainly experience earthquakes in the future. An aging infrastructure and an increase in population density in these regions has led to an increase in the risk of significant damage to buildings, bridges, and utilities in the event of a large earthquake. Recent earthquakes in California and Japan have demonstrated that concrete and masonry buildings constructed prior to the mid 1970's are particularly vulnerable to significant structural damage or even collapse. But not all concrete and masonry buildings pose a threat to life safety and building owners are frustrated with the high costs of retrofitting large inventories of existing buildings, while engineers struggle to identify the truly vulnerable buildings likely to collapse in future earthquakes. Research is needed to help engineers and building owners faced with the challenging task of reducing the seismic risk from existing structures in our urban centres through seismic rehabilitation. The proposed research will endeavour to remove obstacles facing the seismic rehabilitation of concrete and masonry buildings, thereby maximizing the reduction in seismic risk facing Canadians. In particular, the research will focus on three topics designed to contribute to an improved understanding of seismic performance of existing buildings, thereby enabling the design of cost-effective retrofit strategies: (1) the influence of strength degradation on displacement demands; (2) the sensitivity of out-of-plane response of unreinforced masonry walls to in-plane shear damage; and (3) the effect of material deterioration on the seismic performance of existing buildings.