冲击荷载下大型箱涵输水安全性的数值分析

摘要

Safety of water transmission of large-scale box culvert subjected to blast loading is an important topic in civil engineering, study on it involves several factors, such as, propagation of shock wave, interaction between foundation and structure, and so on. A numerical analysis technology was used to simulate the response of a large-scale box culvert under blasting load. Interaction between soil and box culvert was taken into account with a contact model. Arbitrary Lagrangian Eulerian ( ALE) method was used to describe water, and penalty method was employed to simulate fluid-structure interaction. The results showed that under condition of water transmission, ALE description technology can describe the effect of blasting in soil on structure; water can transfer loads to the middle wall of box culvert and mitigate the effect of shock load on the side wall, then improve the whole security of structure; among all the conditions of water transmission, the effect of pressure flow on safety of structure is most obvious.%冲击荷载对大型箱涵输水安全的影响是工程界关注的重要问题,其研究涉及到冲击荷载传播、土—结构物—水相互作用等诸多方面.采用数值分析技术,土与箱涵之间设置接触面单元,水体采用任意拉格朗日欧拉法描述,采用罚方法模拟水与箱涵相互作用,研究了爆炸冲击荷载对大型箱涵输水安全性的影响.研究结果表明:ALE法可以较好揭示土中爆破对输水情况下钢筋混凝土结构物的影响；输水情况下水体能传递荷载到箱涵中墙上,并缓冲冲击荷载对边墙的过大影响,可改善结构整体安全性；有压输水情况对结构物安全影响最为明显.