重力坝纵缝非连续接触地震反应分析

采用非线性动力时程分析方法,通过超载响应分析,初步研究了设纵缝重力坝的抗震能力.运用弥散裂缝模型模拟混凝土在强震下的开裂行为,采用基于罚函数法的接触模型模拟纵缝在动力荷载下的力学行为.对比不设纵缝的计算模型,结果表明纵缝改变了坝体应力分布,降低了坝体的抗震能力.通过对开裂比和抗滑安全系数的分析,判定该设纵缝重力坝段的极限抗震能力为0.6g.

Seismic response analyses of gravity dam considering discontinuous contact of longitudinal joints

The anti-seismic capacity of concrete gravity dam with longitudinal joints is preliminarily studied by using a nonlinear dynamic time-history procedure with overload response analysis. Smeared cracking model is employed to simulate the cracking of concrete during strong earthquake, and the mechanical behavior of the longitudinal joint under dynamic load is simulated by contact model based on penalty method. Comparing with the results of calculation model without longitudinal joints, it is found that the longitudinal joints have changed the distribution of stress in dam and the anti-seismic capacity of the dam is reduced. Based on the analyses of the cracking ratio and the anti-slide safety factor, the maximum anti-seismic capacity of the studied dam with longitudinal joints is evaluated as 0.6 g .