The Study Of Influence Law On The Long-term Safety Of Lining Structure By The Creep Deformation Of Tunnel’s Surrounding Rock Mass

More than30years of Reform and Opening up, with the rapid development of transportation in our country, we have built a large number of tunnel and underground engineering, and made remarkable achievements. At the same time, the tunnel structure which has operated for many years will appear the lining cracking, peeling, and the phenomenon of water leakage etc. disease, affecting the normal use. Therefore, the study of the durability of tunnel structure has become a major issue. Currently for this issue, more research is mainly starting from the angle of the corrosion rate of concrete, but from rock rheological point of view, on the surrounding rock and lining mutual force research is still relatively less. The existing theories are for hydrostatic pressure and circular tunnel, but for the second role of not equal to the analytical solution has not been given.In this paper, based on the rheological theory, the rock mass is treated as a viscoelastic body,and the lining is considered as an elastic body. In theory, the analytical solution is derived of circular tunnel interaction with the time variation in the not equal action of surrounding rock and lining, and further the lining safety coefficient variation with time is derived. For proving the derivation of the theoretical results, the paper used FLAC3D software to do the numerical simulation, also do the numerical calculation for the engineering application of more non circular tunnel, and evaluate its durability.According to the issue " Study on the durability of lining structure by the creep deformation of tunnel’s surrounding rock mass ", the research work in this paper and the obtained results are as follows:1The rock mass is treated as rheological medium, and in accordance with the Burgers model, lining is regarded as an elastic body. The elasticity viscoelasticity correspondence principle is used to derivate the circular the analytical solution of tunnel in the two pressure under the action of surrounding rock and lining force with the time variation. Further, margin of safety has been given for lining Ann coefficient solution theory with time changes. Using MATLAB software, calculate the derivation of the formula.Draw the curve of safety which changes with time;2Using the software FLAC3D, surrounding rock is treated as burgers constitutive model, to simulate the lateral pressure coefficient is1.5, lining structure subjected to the internal force variation with time and application allow should stress rule, evaluated the safety factor of lining.3For circular tunnel, under the same conditions, safety coefficient of theoretical derivation and numerical simulation results are compared and analyzed, and found that the results are consistent with those obtained, verified the correctness of the derived results;4The three heart round arch tunnel is used widely, for Ji Huang high-speed Fo-Ling tunnel as an example.Using FLAC3D software application allows stress method, calculated the safety factor of tunnel operation after100years of2.11, meet the requirements of the lining structure of100years of normal use.