不同横缝状态影响下混凝土重力坝抗爆性能研究

摘要

考虑混凝土重力坝横缝张开状态对大坝内冲击波传播的影响,基于FSI流固耦合数值分析方法模拟水下浅水爆炸冲击波的形成、传播及其与自由面、大坝结构之间的耦合相互作用过程,从混凝土重力坝的动态响应、渐进毁伤破坏过程及大坝损伤耗散能累积特性等方面,对比分析横缝状态对大坝综合抗爆性能的影响机制.结果表明,重力坝横缝张开范围对大坝抗爆性能有重要影响,且表现为加剧大坝动态响应、促进大坝混凝土毁伤破坏区域形成、增大坝体损伤耗能累积量的整体规律,明显削弱了大坝的抗爆性能.%To identify the effect of contraction joint state on the anti-knock performance of concrete gravity dam,numerical simulations based on fluid-solid interaction (FSI) method are conducted,which simulates the formation and propagation of shock wave due to shallow underwater explosion,and its interaction with free surface and dam structure.Considering that the shock wave propagation is influenced by the opening states of the contraction joints in the dam,the impact of the latter on the anti-knock performance of the dam is hence investigated in three aspects,including dynamic response,gradual damage failure process and the accumulation of damage dissipation energy.The numerical results show that the anti-knock performance of the dam is significantly influenced by the opening area of the contraction joint,a larger opening area appears to yield enhanced dynamic response,wider damage area and larger accumulation of damage dissipation energy in the dam,thereby weakening the anti-knock performance of the dam.