结构多点随机地震响应分析及拟静位移计算

给出了大跨度结构多点随机地震响应虚拟激励算法的若干实施细节，并讨论了将拟静位移项用自振振型和广义坐标来表达的做法。表明将拟静位移用自振振型和广义坐标来表达时，可能导致结构位移和内力响应非常大的误差，在实际应用时应予重视。

Seismic random response analysis of Multisupported structures and the quasi-static displacement approximation

For the seismic random response analysis of long span structures subjected to spatially varying ground motion, some details of the pseudo excitation method are provided. Variations of the ground motion due to the wave passage effect, the incoherence effect and the local effect are considered in the analysis. The total responses are decomposed into the quasi-static and the dynamic components, in which the dynamic component is solved based on the mode superposition method. The present paper also discusses the technique that expresses the quasi-static displacements in terms of mode shapes and generalized coordinates. It is found that this expression may cause severe errors for the responses of displacements and internal forces. Therefore, it should be paid more attention in practice.