大断面隧道硐室应力集中系数及拱部衬砌承载力分析

Analysis of stress concentration factor and arch lining supporting force in big-sectional tunnel & chamber

基于弹塑性有限元原理 ,对大断面隧道硐室在简单二维应力场下的应力集中系数的分布进行了分析 ,并对硐室周边最大应力集中系数随扁平率的变化进行了讨论 ;然后采用大位移非线性有限元理论对隧道拱部混凝土衬砌在均布径向荷载作用下的临界承载力和极限承载力进行了计算 ,并讨论了其随矢跨比变化的情况。

Based on principle of elastic-plastic finite element,the distribution of stress concentration factors of big-sectional tunnel & chamber under simple two-dimensional stress field is analyzed while the variation of the maximum stress concentration factor along tunnels and chambers periphery during change of flatness factor is discussed.By means of great-shift nonlinear finite element method,the critical and maximum supporting force of tunnels and chambers arch lining made of concrete under condition of even radial load is calculated.In addition,the variation of the critical and maximum supporting force of arch lining with change of vector-span ratio is discussed.