To efficiently and accurately evaluate the seismic system reliability analysis (SSRA) of cable-stayed bridges subjected to spatially varying ground motions, a direct probabilistic framework was developed in this paper. First, the relevant methods for the structural seismic reliability were presented, including the multiplicative dimensional reduction method, maximum entropy method with fractional moments (FMs), and the product of conditional marginals (PCMs). Second, based on the OpenSees platform, the 3D finite element model of the cable-stayed bridge was established, along with the uncertain structural parameters, stochastic ground motions, and failure modes of each structural component under earthquake loading summarized. Third, considering the double uncertainties of the bridge and ground motions, the nonlinear time history analysis was conducted for the bridge under various scenarios. Finally, the nonlinear seismic response and fractional moment of the structural response were obtained. The maximum entropy method with FMswas used to get the probability density function (pdf) of the structural response, together with the failure probability and reliability index of each component. Considering the correlation between components, the PCMs was used to obtain the failure probability of the bridge under earthquake loadings, and some critical conclusions were drawn.

中文翻译：

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受空间变化地震动影响的斜拉桥抗震可靠性分析

为了有效和准确地评估承受空间变化地震动的斜拉桥的地震系统可靠性分析（SSRA），本文开发了一个直接概率框架。首先，介绍了结构抗震可靠性的相关方法，包括乘法降维法、分数矩最大熵法（FMs）和条件边际乘积法（PCMs）。其次，基于OpenSees平台，建立斜拉桥3D有限元模型，总结地震荷载作用下各结构构件的不确定结构参数、随机地震动和破坏模式。第三，考虑桥梁和地面运动的双重不确定性，对不同场景下的桥梁进行了非线性时程分析。最后，得到了结构响应的非线性地震响应和分数矩。采用FMs最大熵法得到结构响应的概率密度函数(pdf)，以及各构件的失效概率和可靠性指标。考虑到构件之间的相关性，利用PCMs获得了桥梁在地震荷载作用下的失效概率，并得出了一些关键的结论。以及各部件的失效概率和可靠性指标。考虑到构件之间的相关性，利用PCMs获得了桥梁在地震荷载作用下的失效概率，并得出了一些关键的结论。以及各部件的失效概率和可靠性指标。考虑到构件之间的相关性，利用PCMs获得了桥梁在地震荷载作用下的失效概率，并得出了一些关键的结论。