摘要
土与地下结构在强震作用下可能会发生脱离和滑移,对地下结构的动力特性有较大的影响。研究了FLAC软件中接触面单元的力学原理,利用该软件对圆形隧道进行了地震反应模拟分析,对比分析了土与隧道衬砌之间考虑滑移与未考虑滑移两种情况下隧道的动力响应,给出了隧道衬砌不同位置处围岩与衬砌相对滑移量的分布规律。结果表明:考虑土与衬砌之间的滑移时,隧道衬砌的动轴力极值要明显低于未考虑滑移的情况;隧道衬砌的动弯矩极值和动剪力极值要高于未考虑滑移时的结果;圆形隧道的底部与两侧滑移量较大。在实际抗震设计中应考虑土与衬砌之间滑移对隧道抗震性能的影响。
During strong earthquakes,detachment and slippage may happen between soil and underground structure,which has a great impact on the underground structure's dynamic mechanical behaviors.This paper has studied the mechanical principle of the interface element in FLAC software.The seismic response analysis of a circular section tunnel is carried out by the FLAC software.The results with and without considation of the detachment-slippage action in the interface are compared.The distribution regulation of slippage in different positions are given.The results show that: if considering the detachment-slippage action,the dynamic axis force extreme vale of the tunnel lining will be apparently smaller than that of not considering the interface action,but the dynamic moment and the dynamic shear force extreme values will be larger than those of not considering the interface action.Meanwhile the amounts of slippage in the bottom and the two sides will be relatively larger.Therefore,in actual seismic design,the impact generated by the detachment-slippage action should be considered.
出处
《世界地震工程》
CSCD
北大核心
2010年第S1期326-329,共4页
World Earthquake Engineering
基金
公益性行业科研专项经费项目(2008419022)
