This paper illustrates the derivation of an empirical fragility model for residential unreinforced masonry (URM) buildings, calibrated on Italian post-earthquake damage data and compatible with the key features of the Italian national seismic risk platform. Seismic vulnerability is described by fragility functions for three vulnerability classes, then refined based on the building height. To this aim, a clustering strategy is implemented to merge predefined building typologies into vulnerability classes, based on the similarity of the observed seismic fragility. On the other side, a specific procedure is built up to determine the vulnerability composition of the exposed URM building stock, starting from national census data. The empirically-derived model was implemented into the national seismic risk platform and used, together with other vulnerability models, for assessing seismic risk in Italy. The results presented in this paper, consisting of refined typological fragility curves and fragility curves for vulnerability classes, can be also exploited for estimating both expected seismic damage and risk in sites with similar seismic hazard and building inventory.

本文说明了根据意大利震后破坏数据校准并与意大利国家地震风险平台的主要特征兼容的住宅非钢筋砌体（URM）建筑的经验脆弱性模型的推导。易损性功能通过三个易损性类别描述地震易损性，然后根据建筑物高度对其进行细化。为此，基于观察到的地震脆弱性的相似性，实施了聚类策略以将预定义的建筑类型合并到脆弱性类别中。另一方面，从国家人口普查数据开始，建立了一个特定程序来确定暴露的URM建筑库存的脆弱性组成。基于经验的模型已在国家地震风险平台中实施并使用，与其他脆弱性模型一起，用于评估意大利的地震风险。本文提出的结果，包括完善的类型脆弱性曲线和脆弱性类别的脆弱性曲线，也可以用于估计具有相似地震危险和建筑物清单的地点的预期地震破坏和风险。