【摘要】 针对砂砾地层基坑施工的典型支护方式及其支护结构特点,通过建立合理的三维地震反应模型,采用LS-DYNA软件模拟强地震作用下基坑及支护结构的动力稳定性及其失稳突变过程,分析了锚喷支护、地下连续墙加钢支撑支护的耐振特性、钢支撑地震位移及其突变过程和时效特效.结果表明:锚喷支护结构的耐振特性明显优于钢支撑;钢支撑振动位移及其失稳破坏呈现出明显时域特性,且遭受地震后在极短时间内即可发生突变性破坏;地震波的传播方向对结构的稳定性影响很大.更多还原

【Abstract】 Based on the character of typical foundation pit support structure and method in gravel stratum,by establishing reasonable 3-D seismic response analysis numerical simulation,adopting LS-DYNA software,this paper studied the stability and disability mutation process of foundation pit and support structure under intense earthquake action.The results show that vibration-resistence character of bolt-shotcrete is better than that of steel support;vibration displacement and unstable failure of steel support have significant time domain characteristics,and failure happens in very short time;propagation direction of the seismic wave has a great influence on the structure stability.The research results provide reference for construction safety and construction technology of foundation pit in frequent earthquake occurrence area.更多还原