均匀冲击荷载作用下重力坝的损伤分析

Damage Analysis of Gravity Dam under Uniform Impact Load

对于重力坝,远程水下爆炸、大体积山体滑坡等引起的水下冲击波作用可近似视为均匀冲击荷载作用,均匀冲击荷载作用下混凝土重力坝损伤特性较静荷载作用下要复杂得多.本文以非线性显式动力分析程序Abaqus/Explicint为平台,考虑冲击荷载作用下混凝土的高应变率效应,通过建立混凝土重力坝均匀冲击三维模型,对不同冲击荷载下的大坝动态响应进行全性能数值仿真模拟,探讨混凝土重力坝在不同冲击荷载下的损伤.试验结果表明:冲击荷载下大坝损伤模式不仅与大坝自身的动力特性有关,还与冲击能量的大小有关;坝体损伤形式表现为拉伸损伤和压缩损伤,以拉伸损伤为主.

The impact of the gravity dam on the underwater shock wave caused by the long distance underwater explosion and the large volume of the landslide could be regarded as a uniform impact. Damage of concrete gravity dam is much more complex under impact load than under static load. Based on the nonlinear explicit dynamic analysis program Abaqus / Explicit,a 3D model of concrete gravity dam under uniform impact load is built considering the effect of high strain rate of concrete. Furthermore,the full-performance of numerical simulation about dynamic responses of the dam under different impact load is taken,and then the damage of concrete gravity dam under different impact load is discussed. Experimental results show that the damage mode of the dam is not only related with the dynamic characteristics of the dam itself,but also with the size of the impact energy,and the dam damage has two forms of tensile damage and compressive damage,while mainly the former.