Stratum disturbance induced by shield tunnels based on random field theory

The shield tunnel will inevitably cause the disturbance of the surrounding stratum and lead to the deformation of the surface and deep strata. Too large deformation of the surface and strata will threaten the safety of the surrounding construction. Therefore, it is necessary to carry out the studies on the disturbance of the surface and strata in tunnel construction. Firstly, under homogeneous soil conditions, two-dimensional numerical calculation is conducted, and the goodnesses of fit of the Peck's formula and polynomials are used to evaluate the degree of deformation disturbance of the horizontal and vertical strata, respectively. Then, considering the spatial variability of soil parameters, within the Monte Carlo framework, the random analysis is performed for the influences of shield construction on stratum disturbance. The results show that the goodness of fit of the Peck's formula can well reflect the degree of settlement of the horizontal strata induced by tunnels. The goodness of fit of the polynomials can well reflect the degree of horizontal deformation of the vertical strata affected by the construction. The spatial variability of soil modulus has a great impact on the stratum disturbance induced by the shield tunnel, and the larger modulus will restrain the disturbance induced by the shield tunnel, but on the whole, the greater stratum disturbance will occur when it is closer to the shield tunnel. The results can provide a useful reference for the design and construction of similar projects.