| Shield tunnel has been widely used in urban metro construction。Large scale section,high hydrostatic water pressure,long distant excavation of shield tunnel is becoming the problem that must be solved immediately. Based on the super large scale segment lining (φ14.5m) of Nanjing Changjiang Tunnel, numerical simulation and laboratorial model test taking geometric similarity ratio C_L=25 and bulk density similarity ratio C_γ=1 as the base is used as the research means to study the mechanical characteristic of the lining with different assembling plan under different water and soil pressure, the failure characteristic of the single lining working under high water pressure is also studied.Non-uniform water pressure device is exploited, which offer the key support to study home the water and soil pressure on segment lining, and actualize separate control of them.Main content of the dissertation are as follows:(1) Numerical simulation is carried out of the lining with different assembling plan according to the computational conditions, and the inner force, deformation which control the design is obtained, meanwhile the result of the model test is validated.(2) Mechanical characteristic and its changing laws of the segment lining under different hydrostatic water pressure is studied.(3) The reaction of the lining under soil pressure due to different cover depth of the stratum and lateral coefficient is studied, and the effect of different stratum circumstances to the lining is analyzed.(4) Mechanical characteristic of the lining with seven kinds of assembling plan under various working conditions is synthetically compared, and mechanical characteristic of the lining with different assembling plan is also studied, meanwhile the best assembling plan is chosen.(5) Failure test of the lining is done under 50 meter high hydrostatic water pressure, and the failure characteristic is obtained which can't be done by numerical simulation.
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