多点地震激励下大跨度桥梁动力可靠度研究

动力可靠度理论已经有了很大进展，但是在工程中却尚未获得广泛应用，结构动力响应功率谱计算的复杂性是造成这一状况的重要原因。本文将虚拟激励法引入大跨度桥梁抗震可靠度分析。用随机振动虚拟激励谱分析突破以往计算效率低下的瓶颈，在理论．卜是精确的算法，并能方便地处理地震地面运动变化产生的空间效应。研究结果表明，基于虚拟激励法进行大跨度桥梁动力可靠度分析是一条有前景的途径。

Seismic Reliability of Long-Span Bridges under Multi-Support Excitations

While the dynamic reliability theory has achieved important progress,its applications to engineering fields are still quite limited.An important reason is the complexity of the random vibration analysis.In this paper,the recently developed pseudo excitation method(PEM) was used in the reliability research of long-span bridges in inhomogeneous random fields.The formulation and example given in the paper show that the pseudo excitation method is not only an exact method for random vibration analysis,but also is very efficient even for complex long-span structures subject to multiple seismic excitations.Therefore the dynamic reliability analysis combined with PEM provides an innovative way for such problems.