Study on Finite Element Numerical Simulation of Shallow Buried Tunnel Based on Displacement Back Analysis

In order to more precisely to acquire the mechanics parameter of surrounding rock for finite element modeling, on the basis of a tunnel of Longlin~Baise expressway in Guangxi Zhuang Autonomous Region, the method of acquiring the mechanics parameter of surrounding rock based on displacement analysis was applied. According to the field measurement raw data, the equivalent elastic modulus and lateral pressure coefficient was acquired by means of the displacement back analysis program, as BMP90.In the finite element modeling analysis, the equivalent elastic modulus and lateral pressure coefficient and parameters suggested from related standard was applied. Compared the calculation results and the field measurement raw data, and it shows that the calculated results based on the back analysis is more consistent with the field measurement raw data, and the surrounding rock parameters based on the displacement back analysis is more coincide with the real engineering. The study can provide certain reference for selection of mechanics parameters of surrounding rock.