Research and analysis of comparative tests of optimization of methods for reinforcing soft surrounding rock of tunnel

In order to solve the problem of optimum supporting design of tunnel engineering with soft surrounding rock, a similar material of model of which the mechanical curve is similar to the origional rock is developed. The physical models corresponding with the cases which are usually used in soft rock engineering such as bolt supporting case, bolt and jetting supporting case, lengthed bolt and jetting supporting case, are made. As well as the bare tunnel case, the four models form a 3D model and are put into the large scale real triaxial physical model machine. So the research on supporting design of soft rock tunnel is base on the same boundary condition of model. The test results demonstrate that various supporting methods lead to various over loaded abilities and various failure character. The similar material is fit for the trait of large deformation of soft rock. The research provides reliable foundation for supporting design of soft rock tunnel as well.