| Shallow tunneling method has been adopted for city underground engineering which does not meet the condition of openly cut method. Its utility and superiority of some aspects have been approved by previous engineering practice and it is widely used now. It is important to consider the influence of shallow tunneling upon environment (such as surrounding stratum, pipeline, building, etc) for its being mostly used in city underground engineering. During the excavation of underground engineering, three-dimensional size of earth excavation at every step should be decreased relevantly and the time of exposure at every step of excavation should be reduced. Those are the principle countermeasures on the soil stabilization and deformation in consideration of space-time effect and making full use of the potential to control the displacement of layer of earth in soil body. Firstly, the creation, development and some basic principles of shallow tunneling method are introduced and the rough definition of the space-time effect is given in this thesis. The present research status of heterotaxy by the excavation of tunnel is introduced, including empirical formula method, numerical method, analytical method and so on. Then, the fundamental theories of tunneling, FEA(finite element analysis) of tunneling and constitutive model for soil are summarized. Finally, a FEA software PLAXIS is used to carry on three-dimensional FEA based on the practical engineering. In the calculation process, Mohr-Coulomb elastic-plastic constitutive model is applied for soil mass and the influence of various conditions is fully considered. Generally speaking, two parts are included in the thesis. Firstly, the space-time effect of heterotaxy induced by the excavation of tunnel is discussed. Secondly, the control effect to heterotaxy with different conditions (grouting location, the range of grouting, footage of excavation and thickness of shotcrete) is analyzed and the effects are reasonably evaluated.
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