The Parameter Back Analysis of Rock Mass Based on Orthogonal Design

Equivalent parameter of rock mass is more often used in deformation calculation of tunnel surrounding rock. The motivation for this paper is to estimate equivalent parameters of rock mass in a tunnel project under construction. A new statistic that represents the difference between measured displacements and simulation results is constructed. Orthogonal experimental design and multiple factor variance analyzing formulas are applied to inverse rock mass parameters. The parameters of rock mass sufficiently close to the tunnel project are back analyzed by minimizing the error function. Variance analysis indicates that Elastic modulus is the most sensitive factor to deformation calculation.