在瞬态载荷作用下地下结构非线性动力反应分析

Nonlinear Dynamic Analysis of Underground Structures under Transient Loads

针对实际地下工程中普遍存在的材料非线性以及半无限介质域的处理问题，给出了基于时间有关基本解的时域边界元法与非线性动力有限元法的耦合方法，将该耦合法推广到计及材料非线性的地下结构与周围介质动力相互作用的研究领域．文本应用给出的方法计算了有无支撑结构两种情况下一马蹄形截面地下防护结构受爆炸波作用时塑性屈服及动力反应历程，并与线弹性情况进行了比较分析．

The paper presents the extension of the combination of boundary element method(BEM) with finite element method(FEM) to nonlinear dynamic analysis of underground structures. The structure and a small finite portion of surrounding medium are treat6d by FEM while the semi-infinite domain by BEM,in which all formulations are developed in time domain. In this way, one is able to consider the nonlinear behavior of the structure and the surrounding medium.Meanwhile, an effective algorithm to solve the nonlinear governing equations is also developed. Nonlinear analyses of both lined and unlined cavities are undertaken to demonstrate the efficiency of the present method.