公路隧道衬砌有限元分析

衬砌内力的计算是公路隧道设计的关键问题,计算结果的准确性会影响结构的安全性与经济性.文中采用有限元分析软件MIDAS用有限元法计算衬砌的内力和变形.衬砌结构采用梁单元,围岩抗力采用面弹簧单元模拟,墙脚支座用点弹簧单元模拟,计算荷载为竖直方向和水平方向围岩压力.通过分析得到衬砌最大位移的大小和位置,衬砌结构的内力分布及数值大小.另外,根据分析结果得到抗力最大值为侧墙距墙脚1/3处,图形呈镰刀形分布,与经验确定的抗力分布图形式一致,分析结果和手算结果规律一致.

Analysis of highway tunnel lining with finite element method

Calculation of internal force of lining is the key problem in the design of highway tunnel. The accuracy of the calculation results will affect the safety and economy of the structure. A finite element software MIDAS is used to analyze the internal force and deformation of lining. The lining structure consists of beam elements, the surface resistance of rock spring element to simulate, a support spring element to simulate, load calculation for the horizontal and vertical surrounding rock pressure. Through analysis the location and data of the maximum displacement are obtained as well as the distribution and values of internal force. The maximum resistance is at the side wall of distance foundation 1/3. Graphics is sickle shaped in the distribution map form, which is consistent with empirically determined. The results of the analysis and calculation results are consistent.