地下工程地震动力响应及抗震研究

 应用改进的Newmark隐式积分法，采用无限元动力人工边界，研究西藏扎墨公路高烈度地震区嘎隆拉隧道地震动力响应，分析隧道抗震层的减震机制，数值模拟橡胶和泡沫混凝土两类材料抗震层的减震效果。计算结果表明：抗震层虽不能从根本上改变隧道的动力响应，但由于它本身的隔震缓冲作用，能够对衬砌起到较好的隔震效果；两类抗震材料隔震效果相差不大，但考虑到耐久性和经济性，推荐采用泡沫混凝土作隔震材料。研究成果对高烈度地震区地下工程稳定性分析具有一定的借鉴意义。

RESEARCH ON EARTHQUAKE-INDUCED DYNAMIC RESPONSES AND ASEISMIC MEASURES FOR UNDERGROUND ENGINEERING

Based on improved Newmark¢s implicit integration method，the earthquake-induced dynamic responses of Galongla Tunnel along Zhamo Highway in Tibet are studied using infinite element dynamic artificial boundary technique；and aseismic mechanism of seismic isolation layer is analysed. Furthermore，the shock absorption effects of two kinds of seismic isolation layers，which are made of rubber and foam concrete respectively，are studied and compared those with numerical method. The results show that better shock absorption effects can be achieved because of the good isolation and cushioning effects of the seismic isolation layer despite that the dynamic response of the tunnel cannot be changed essentially. It also can be seen that there are small differences in shock absorption effects between two kinds of seismic isolation materials；however，foam concrete is recommended because of its durability and economy. Results of this research can provide certain references to stability analysis of underground engineering in highly seismic regions.