| With the rapiddevelopment of the national metropolitan construction, the urban metro, municipal road tunnel and other underground engineering have been sprung up. Tunnel construction inevitably causes stratum displacement and deformation, which result in unfavorable effect on safety of the surrounding ground buildings and underground pipelines. In this dissertation, based on the stratum deformation mechanism caused by tunnel excavation, by using the stochastic medium theory, consolidation theory of soil and Mindlin elastic theory, the time-space effect of stratum deformation as well as their correlated issues caused by the mined tunneling method and shield tunneling method is researched systemically, and the corresponding equation is deduced. Then, the effect factors and their degree of the stratum deformation caused by tunnel excavation are discussed in mechanism. Finally the reliability calculation of stratum deformation is discussed according to the probability theory.(1) Based on Stochastic Medium Theory, the stratum deformation united equation considering time-space effect is gained, which can take into account such factors as repeated construction and cessation, the change of excavating speed, the different geological condition, single-arch tunnel with multi-section excavation method, the parallel or overlap construction of two or more tunnels, excavation in semi-infinite space, and so on. And then the real-time calculation of stratum deformation caused by tunnel excavation can be realized.(2) The method on calculating parameter of the stratum deformation for tunnel construction is discussed. The time effect of the displacement of tunnel surrounding rock is analyzed, the treatment is provided for the absence of data because of the monitor lag. So the method of calculating stratum losses is put forward. Furthermore, the Dynamic Back Analysis Method on the calculating parameter of the stratum deformation is studied.(3) The formula of the stratum deformation used for the tunnels with such cross-section shapes as the circle shape, the elliptical shape, the horseshoe shape and the arbitrary shape is deduced, and the simplified calculated method for these cross-section shapes which meet the requirement of engineering application is presented.(4) The time-space effect of the soil effective stress caused by the dewatering is discussed, in terms of the mechanism that the unit volume would vary with the change of unit effective stress, the formula of the stratum deformation induced by the water reducing is gotten. And, the calculating equation of the stratum deformation, which considered the water reducing effect relating to the tunnel excavating process, is obtained. Then the time-space effect of stratum deformation caused by dewatering is solved finally.(5) According to Mindlin Elastic Theory, the mechanical model for shield tunnel is set up, which take into account the shield driving, and then, the formula of the stratum deformation around the tunnel because of both the additional press from the shield working face and the fraction between the shield wall and the soil is deduced. Then the accurate calculation of stratum deformation surrounding the shield on different position and at different moment is resolved.(6) Based on the Reliability Theory, Stochastic Medium Theory and other related theories, the reliability of the calculating result of stratum deformation for tunnel excavation is inspected, which is influenced by the working parameter and geotechnical parameter. As the statistical data of the calculating parameters is deficient now, the parameter samples are produced by computer based on the Monte-Carlo Method. Then the reliability calculation of stratum deformation caused by tunnel excavation is realized.(7) Based on both VC++6.0 and MATLAB, the application program for calculating the stratum deformation, which take the time-space effect into account, is explored. Not only could the program realize the calculation based on both the certain formula and reliability theory of the stratum deformation resulting of such factors as Mined Tunneling Method, Shield Tunneling Method, Multi-Separated Excavation Method and the dewatering, but also realize the multi-dimensions display in program. Furthermore the program could realize the parameter restore and back analysis. Finally, together with the application in some engineering, the reliability of the program is proved.(8) The factors governing the time-space law of the stratum deformation caused by tunnel excavation is discussed quantitative, they are longitudinal excavation step, differences between oppositely excavating and back excavating, divisions of cross-section, excavation speed, dewatering depth, distance from the dewatering well to the tunnel, additional press from the shield working face, the fraction between the shield wall and the soil, and so on. The quantitative analysis provides evidences to take the effective construction measures to restrict the stratum deformation and protect the safety of the surrounding ground buildings and underground pipelines.
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