反应谱离散性对梁桥概率地震需求预计的影响

以一座三跨非规则钢筋混凝土连续梁桥为例，选择2组实际地震波作为输入地面运动，通过IDA分析探讨地震波反应谱的离散度对于梁桥结构概率地震需求预计的影响，得到以下结论：实际地震波的反应谱离散度与桥梁结构概率地震需求预计的离散度密切相关；针对基于概率理论的PBEE和PBSD，合理的选择实际地震波进行动力分析，可以使地震需求的概率分布更加符合实际情况，提高概率地震需求预计、易损性曲线等计算结果的精确性和计算效率。

Effects of Response Spectra Dispersion of Earthquake Ground Motions on Probabilistic Seismic Demand Assessment of Bridge Structures

A three-span regular continuous RC girder highway bridge and two bins of real accelerograms were selected for incremental dynamic analysis to study the correlation of the dispersions of response spectra of earthquake ground motions and probabilistic seismic demand assessments of bridge structures. It is found that the dispersions of seismic demands are closely related to the dispersions of response spectra of selected ground motions. The rational selection of real earthquake ground motions to be rationally chosen for dynamic analysis can make the probability distribution of seismic demands in accordance with the real situation and improve the computational precision and efficiency of the probabilistic seismic demand assessment and fragility curve for performance-based earthquake engineering and seismic design of bridges based on probability theory.