在分析公路隧道初期支护可靠性方面,蒙特卡罗法具有较高的精度。由于工程结构破坏概率通常较小,这就要求采用蒙特卡罗方法时必须要有足够大的抽样模拟总数才能给出正确的估计,利用方差减缩技术中的对偶抽样技巧可以迅速的降低抽样模拟次数。基于有限元模拟中隧道初期支护极限状态的功能函数的分析,依据公路隧道设计规范,确定了初期支护可靠度分析的极限位移的功能函数。并且利用APDL语言,编制了调用ANSYS建模求解模块分析隧道可靠度的程序,基于对偶抽样蒙特卡罗有限元模拟分析了深埋隧道初期支护的可靠性。
The Monte Carlo Finite Element Method is superior to other methods when it is used to analyze the reliability of the initial support of a highway tunnel. A correct reliability index could be collected when an adequate number of samples is selected because the failure probabilities of engineering structures are usually very small. The amount of sampling could sharply decrease by using the dual sampling method. During the comparison, the supporting role exaggeration of the line element, which is used in the FEM model to simulate the initial lining and rock bolt, was found by FEM simulation. The lining element reaction forces which were greater than usual were reported in FEM analysis results. Deeply Buried Tunnel Reliability Analysis was developed on the platform of ANSYS.