This paper presents a preliminary seismic risk screening tool to identify buildings whose superior structural and non-structural seismic performance in regions of low seismicity can be assessed based on several key attributes. The tool is designed to exempt buildings from detailed seismic risk assessment if key exemption criteria are met. The exemption criteria are based on: a seismic categorization system linked to anticipated building damage and seismicity; whether or not the building was designed using modern seismic design provisions; and the remaining time that the building will be occupied. The tool also provides a second list of criteria, which if satisfied, will automatically trigger further detailed seismic risk assessment. The decisions rendered by the tool regarding the expected seismic performance of a building are evaluated against the next level of seismic risk screening tool to ensure the consistency. A flowchart is presented to facilitate adoption of the tool by practicing engineers and other end-users.

The National Research Council Canada (NRC) recently developed a semi-quantitative seismic risk screening tool (SQST) for existing buildings in Canada. The SQST aims to supersede the Manual for Screening of Buildings for Seismic Investigation developed by NRC in the early 1990s. The SQST consists of three key components: (1) a structural scoring system that quantitatively assesses the structural seismic risk based on probability of collapse; (2) a non-structural component scoring system that qualitatively assesses the seismic risk of non-structural components based on seismic demand; and (3) a ranking procedure that prioritizes potentially hazardous buildings for seismic evaluations and possible upgrading. The SQST intends to inexpensively identify and exempt buildings with acceptable life safety risk and optimize the allocation of resources to assess the seismic risk of portfolios of buildings. Seismic screening with the SQST can be completed with either paper-based screening forms or a web-based application. The applicability of the SQST is demonstrated by conducting a pilot study for 33 existing buildings across Canada.

The National Research Council of Canada (NRC) has recently developed a Semi-Quantitative Seismic Risk Screening Tool (SQST) to supersede the 1993 NRC Manual for Screening of Buildings for Seismic Investigation. The proposed screening tool incorporates a methodology for estimating global seismic risk of existing buildings associated with failure of their non-structural components. The methodology assesses global seismic risk using a qualitative yet comprehensive scoring system. The scoring system consists of a global non-structural component score and acceptable threshold scores. The global score is based on the most critical components. It combines a basic score with score modifiers for key parameters affecting the seismic response of non-structural components. The acceptable threshold score is based on the building’s consequence of failure, the building’s importance category, and the component factor. The scoring system is calibrated to be consistent with the seismic risk acceptance criteria previously developed for preliminary seismic risk screening of existing buildings, based on Canadian seismicity, building age, remaining occupancy time, and consequences of failure.

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The National Research Council Canada recently developed a multi-criteria and multi-level framework for seismic risk management of existing buildings in Canada. One of the key criteria in this framework is benchmark NBC edition, which refers to the applicable edition of National Building Code of Canada (NBC) in which significantly improved seismic requirements were adopted and enforced. Since post-benchmark buildings are expected to demonstrate satisfactory seismic performance, they may be exempt from structural seismic risk assessment. This paper identifies benchmark NBC editions for 17 model building types in Canada. The identification starts by tracking major seismic improvements in the United States benchmark codes and standards. These improvements are then mapped to applicable NBC editions and relevant design standards. Provincial building code editions corresponding to benchmark NBC editions are also identified. The benchmark NBC editions and corresponding provincial building code editions help building owners quickly identify and exempt post-benchmark buildings with acceptable seismic risks and thus allocate resources to the buildings with potentially unacceptable seismic risks.