Safety Adaptability Evaluation And Engineering Test Verification Of TBM Tunneling In Composite Stratum

With the development of China's transportation infrastructure,the central and western regions have built a large number of Railways and highways mainly to strengthen the trunk lines;while the eastern region is mainly to relieve the ground traffic pressure and build subway,and whether it is railway or highway construction,tunnel excavation is required,and TBM method is the first choice in technology,speed and cost.However,due to the late start of TBM in China,the accumulated experience is not sufficient,and many risk disasters will be encountered in the actual excavation process,resulting in economic losses,even casualties.Therefore,it is necessary to conduct a comprehensive analysis of the safety adaptability of TBM excavation,and calculate the geological adaptability before excavation to guide the construction.In this paper,the combination of theoretical modeling and model test is used to conduct in-depth study on the adaptability of TBM driving safety.The innovative achievements of this paper are mainly as follows:(1)Based on the investigation of domestic TBM construction cases and combined with relevant research results,15 indexes of TBM tunneling safety adaptability are selected.According to the parameters of TBM itself,geological parameters and risk parameters,the evaluation index system of TBM tunneling safety adaptability is established.(2)According to the analytic hierarchy process,the weights of open TBM and shield TBM are sorted,and then the membership function of each index is determined.According to the fuzzy comprehensive evaluation method,the weight and membership function are calculated to get the final adaptability of TBM driving safety,and the adaptability level is determined according to the adaptability.(3)Carry out the geological model test of safety adaptability of TBM excavation,simulate the whole process of TBM excavation,record the excavation parameters,geological parameters and risk parameters,and check the accuracy of the evaluation model of TBM excavation safety adaptability according to the data of surface settlement,convergence deformation and stress release in the tunnel The evaluation model has a certain practicability.(4)This evaluation model is applied to evaluate the safety adaptability of TBM driving in haipoqiao Xiaocun station,and the evaluation grade is "strong adaptability".According to the surface settlement data of excavation and the engineering practice,it shows again that the evaluation model is accurate and practical.