This research conducts a thorough reevaluation of seismic fragility curves by utilizing ordinal regression models, moving away from the commonly used log-normal distribution function known for its simplicity. It explores the nuanced differences and interrelations among various ordinal regression approaches, including Cumulative, Sequential, and Adjacent Category models, alongside their enhanced versions that incorporate category-specific effects and variance heterogeneity. The study applies these methodologies to empirical bridge damage data from the 2008 Wenchuan earthquake, using both frequentist and Bayesian inference methods, and conducts model diagnostics using surrogate residuals. The analysis covers eleven models, from basic to those with heteroscedastic extensions and category-specific effects. Through rigorous leave-one-out cross-validation, the Sequential model with category-specific effects emerges as the most effective. The findings underscore a notable divergence in damage probability predictions between this model and conventional Cumulative probit models, advocating for a substantial transition towards more adaptable fragility curve modeling techniques that enhance the precision of seismic risk assessments. In conclusion, this research not only readdresses the challenge of fitting seismic fragility curves but also advances methodological standards and expands the scope of seismic fragility analysis. It advocates for ongoing innovation and critical reevaluation of conventional methods to advance the predictive accuracy and applicability of seismic fragility models within the performance-based earthquake engineering domain.

翻译：本研究对地震易损性曲线进行了全面重评估，采用序数回归模型以取代因其简洁性而广泛使用的对数正态分布函数。研究系统探讨了各类序数回归方法间的细微差异与内在联系，包括累积模型、序贯模型和相邻类别模型，以及融合了类别特异性效应与方差异质性的增强版本。基于2008年汶川地震桥梁震害实测数据，本研究采用频率学派与贝叶斯推断方法实施建模，并运用代理残差进行模型诊断。分析涵盖从基础模型到具有异方差扩展及类别特异性效应的共十一种模型。通过严格的留一交叉验证，具有类别特异性效应的序贯模型展现出最优性能。研究结果凸显了该模型与传统累积概率单位模型在损伤概率预测上的显著差异，主张向更具适应性的易损性曲线建模技术转型，以提升地震风险评估精度。综上所述，本研究不仅重新审视了地震易损性曲线拟合的挑战，更推进了方法学标准并拓展了地震易损性分析的研究维度。研究倡导在基于性能的地震工程领域持续开展方法创新与对传统模型的批判性重评估，以提升地震易损性模型的预测精度与适用性。