受演变随机激励结构响应的精细逐步积分法

High precision direct integration scheme for analysingstructural nonstationary random responses

对于受演变随机激励的线性多自由度体系，给出计算其非平稳响应的高效高精度方法。先用虚拟激励法将随机荷载化为确定性荷载；然后构造一种特别快速精确的无条件稳定显式逐步积分格式，求出时变功率谱响应的离散数值解，并通过算例与Ｎｅｗｍａｒｋ法、Ｄｕｈａｍｅｌ法在精度、效率上进行比较，表明本方法具有显著的优越性。

A highly efficient and accurate direct integration scheme for analysing the non-stationary responses of linear MDOF structures subjected to evolutionary random excitations isproposed. The random excitations are first transformed into pseudo excitations before theresulting deterministic equations of motion are solved by the proposed high precision directintegration scheme. Two examples are given to show the advantages of this method over theNewmark and Duharnel methods when computing the time-dependent power spectral densities ofthe structural responses.