Anti-breaking Mechanism And Design Parameters Research On High-speed Railway Tunnel Engineering Through The Wenchuan Seismic Fracture Zone

In recent years, with the rapid development of railway engineering, the tunnel project has become increasingly important. In Chinese western, the geological condition is complex, and fault zone motion emerges frequently. It is inevitable to be encountered with tunnels constructed across faults in the design of tunnels. Grasping the geological condition and seismic situation of the tunnel engineering, analyzing the danger level of a fault fractured zone and ensuring that the railway tunnel project in the normal function of earthquake are meaningful to the engineering construction of West China. Based in Chengdu-Lanzhou railway tunnel for the study, we research anti-breaking methods of tunnels which across the fault zone, and then those methods are analyzed and estimated by FEM.Firstly, the development overview and calculation theory of underground structure across the fault are summarized in this paper. Sum up all kinds of anti-breaking and anti-damping measures in the underground project. Collect the tunnel damage information of5.12WenChuan earthquake. Summarize the relationship between the degree of tunnel damage and the epicentral distance. Secondly, gather seismic parameters of historical earthquake in China’s western region, deliberate the linear regression relation between seismic magnitude and parameters. Then, Present the anti-breaking method including the design of seismic joint and expanded excavation technique.On the basis of rational anti-breaking methods, the typical form of lining structure of active fault is chosen, the numerical model of fault section surrounding rock-structure system is built and by simulated calculation, the property of new lining structure is confirmed. The comparative analysis is performed based on the different aseismatic joint interval, the different dip angle and different width of fault. The internal forces, the displacement response of the tunnel lining as well as the damaged area of surrounding rock are supplied. Finally, utilize the numerical simulation to evaluate regular reinforcement scheme, high tensile reinforcement scheme and optimization scheme through the tunnel deformation and fracture discipline, and then comprehend the respective deformation and destruction.