Holistic seismic assessment of Eastern Canada's old unreinforced masonry structures

一场破坏性的地震袭击加拿大东部的中高地震活动城市，其影响可能是灾难性的。这在很大程度上是由于在人口众多的城市中心，脆弱的旧的（或未规范的）未经加固的砖石建筑（URM）占主导地位，这些建筑在学校、消防站、发电厂和国家一级的遗产（或历史）建筑中占有相当大的份额，对我们的安全、经济和文化特征构成严重威胁。过去的研究虽然提供了信息，但没有广泛和系统地处理这一关键问题，这破坏了备灾和灾后恢复。这个改造项目的长期目标是提高加拿大东部旧URM建筑的抗震能力，以减少故障概率、后果和恢复时间。为此目的，需要有效的地震风险模型和减灾战略，但由于现有建筑物库存分散，对旧的URM结构特征的了解有限，当地高频地面震动的影响未知，以及缺乏专门的数字评估准则，目前还没有有效的地震风险模型和减灾战略；工程师们仍然不恰当地依赖于钢/混凝土分析技术。该项目通过三个具体的短期（<5年）目标，将重点放在历史URM结构上，以解决这些关键的研究空白。历史URM结构是具有附加遗产价值的旧建筑的一个更好的记录和更容易接近的类型子集。通过类型学分析选择具有代表性的建筑，通过将过去的建筑清单统一到一个新颖的开放访问网络平台，使我们能够专注于一些关键资产，并与不同的专家分享新的知识；ii -表征：通过实地采集和现场检查/测试收集现场证据，阐明结构特性，以证实地震分析；iii -评估：通过知情的数值模型评估地震反应，以评估当地地震活动的影响、经常性破坏机制以及认知/统计不确定性对预测的影响，使我们能够确定合适的分析方法。在短期内，这一创新项目将产生关于加拿大东部历史URM结构的新知识，也适用于当地的旧URM建筑，并提高工程师评估其地震反应的能力，为数值模拟和改进改造设计提供缺失的指导。从长远来看，我们的原始贡献有可能指导区域地震风险评估和减灾工作，并根据加拿大的战略优先事项（例如联合国可持续发展议程）和承诺（例如仙台减少灾害风险框架）延长旧URM建筑的寿命。通过这个项目，HQP将在日益增长的需求领域接受独特的培训，使他们在学术界内外都能脱颖而出。

The impact of a damaging earthquake striking Eastern Canada's medium-to-high seismicity cities could be catastrophic. This is largely due to the predominant presence in populous urban centres of vulnerable old (or pre-code) unreinforced masonry (URM) buildings - a relevant share of schools, fire stations, power plants and heritage (or historic) constructions also at the national level - posing a serious threat to our safety, economy and cultural identity. Past research, albeit informative, has not extensively nor systematically addressed this key issue, which undermines disaster preparedness and recovery. The long-term (>5 years) goal of this transformative program is to enhance the seismic resilience of Eastern Canada's old URM buildings, for reducing failure probabilities, consequences and recovery time. To this end, effective seismic risk models and mitigation strategies are needed, but not yet available, given the scattered nature of existing building inventories, the limited knowledge of the structural features of old URM structures and the unknown effects of local high-frequency ground-shakings, as well as the absence of ad-hoc numerical assessment guidelines; engineers still inappropriately rely on steel/concrete analysis techniques. This program addresses these key research gaps by focusing on historic URM structures - a better documented and more accessible typological subset of old buildings with added heritage value, through three specific short-term (<5 years) objectives: I-classification: select representative buildings via typological analysis, enabled by unifying past building inventories into a novel open-access web platform that will allow us to focus on a few key assets and share new knowledge with diverse experts; II-characterization: elucidate structural properties by gathering field evidence via reality capture and in-situ inspection/testing, to substantiate seismic analyses; III-evaluation: assess seismic responses via informed numerical models, to evaluate the impact of local seismicity, recurrent damage mechanisms and the influence of epistemic/statistical uncertainties on predictions, enabling us to identify suitable analysis approaches. In the short-term, this innovative program will produce new knowledge on Eastern Canada's historic URM structures, also applicable to local old URM buildings, and enhance the capacity of engineers to evaluate their seismic response, providing missing guidance on numerical modelling and improving retrofit design. In the long-term, our original contributions have the potential to guide regional seismic risk assessment and mitigation efforts and increase the lifespan of old URM buildings, in line with Canada's strategic priorities (e.g. United Nations 'Agenda of Sustainable Development) and commitments (e.g. Sendai Framework for Disaster Risk Reduction). Through this program, HQP will receive unique training in fields of increasing demand, enabling them to excel within and beyond academia.