Supporting Effect And Application Technique Study Of Rock Bolt In The Large Deformation Broken Rock

With the rapid development of the national economy and the implementation of the western development strategy, the highway construction is developing to the mountain area with the complex topography, complex geological conditions; big tunnel is emerging through the large deformation broken rock; it is very urgent and important to adopt effective measures to support the tunnel. While rock bolt is one of the main forms maintaining tunnel stability in underground engineering, it plays an important role in the tunnel, especially through the large deformation broken rock; the reinforcement effect of the rock bolt is obvious. However, supporting technology and theory research on the rock bolt is still on the stage of development, and it is in need of further research and analysis, especially in large deformation mechanism of tunnel.The main research method is based on the numerical simulation calculation of FLAC 3D, and the research content is the mechanism analysis of rock bolt in the tunnel through the large deformation broken rock. The conclusion is mainly in the following aspects:1,According to compare the size of the tunnel deformation and the plastic zone by the numerical simulation calculation based on the selection of different material constitutive model, it is achieved that the strain hardening-softening model is appropriate to reflect the character of the tunnel deformation for the large deformation broken rock.2,Through the numerical simulation calculation of rock bolt, determine that the support role of rock bolt is notable, and it is effective to control tunnel deformation. The support mechanism of the rock bolt under this condition is the results of common action by combination arch action and suspension action.3,By analyzing the application effect of rock bolt in the practical engineering, validate the support role of rock bolt. According to comparing the results of the numerical simulation calculation with the results of the monitoring and measuring, achieve the difference and sum up the reason of tht difference.