Estimated justification of the bearing capacity of the lining when opening auxiliary workings in conditions of local freezing of the rock mass

Abstract

For performance of works on the device of tunnel constructions in the conditions of the water-saturated unstable soils having character floating, their stabilization and strengthening is provided. During the construction of combined ventilation and technological failure of the existing subway, planned for the production of construction and installation works by mining in water-saturated fine Sands, provides for the implementation of measures to freeze the soil mass. For the safe construction of the workings of the decision on the implementation of the calculations and mathematical modeling of the impact on the lining and tongue and groove fencing in the production of works for freezing, opening the lining and thawing of the soil array. The article presents the results of analytical studies of the state of the rock sand massif in freezing conditions. The algorithm of numerical realization of the spatial inelastic problem using the method of finite differences and finite elements of MacCormack of the second order for dynamic problems is used and implemented to calculate the structure on mechanical effects. The finite element method is used in the Lagrange formulation of dynamic and static problems. The model of concrete and soil, described by the theory of plastic flow for shear, taking into account the rate of loading under volumetric deformation, is applied. To solve static (quasi-static problems), the method of establishing an explicit implementation or a quasi-static method in the absence of inertial terms is used. The layered two-phase medium, each layer of which is homogeneous and isotropic, is considered. This medium simulates the behavior of water-saturated soil, one phase of which is in the melt, and the other in the frozen state.