Study On Surrounding Rockmass Stability And Support Parameter By Open Type TBM Excavtion

TBM construction method in deep, long tunnel than drilling and blasting method has great advantages, Because when the tunnel buried deep, the length is too long, hole diameter is large, using drill and blast method will take a long duration, especially when the duration of the economic and ecological environment have a significant impact on the excavation by the constraints they face in the face velocity, environmental protection, efficiency, safety and other issues, will become the preferred use of TBM.Stability of surrounding rock has always been an important research project, evaluation results of the correct stability of surrounding rock is directly related to success or failure of underground works. Therefore, open-type TBM construction method in the surrounding rock stability analysis and research on the great practical significance.In this paper, Zhongtianshan tunnel in Nanjiang railway line as support, field test and numerical simulation studies as the main means of comparing the two, confirmed, mainly the following aspects were analyzed.(1)TBM tunnel excavation on the rock-breaking process of analysis, and based on the deformation characteristics of the study, and discusses the factors influencing the stability of surrounding rock.(2)Through this investigation, come to different rock mass, joint set number and the joint combination of the nature of the relationship between the surrounding rock stability relationship.(3)Through the ultrasonic field test, obtained for different rock TBM construction impact on the situation surrounding the integrity of the range and coefficient, and discuss the integrity of surrounding rock stability factor and the relationship between.(4)Construction of the open type TBM numerical simulation, obtained for different rock conditions TBM construction sphere of influence, and field test results compared to amend.(5)The results of the test results and comparison analysis, support parameters; and support parameters, and according to the actual situation on site specific support methods and support measures.