Reduction of additional pressure from ground construction on the subway escalator tunnel

Abstract

The study considered options for reducing the additional pressure from the construction of a single-storey building on the underground structures of a deep shallow metro station. In the 3D formulation, the efficiency of the unloading «bridge» over the escalator tunnel was evaluated by the finite element method. It was found that the stiffer the grillage plate of the unloading «bridge», the more effectively the additional pressure from the building is transferred to the soils below the bottom of the escalator tunnel. However, in this case it is impossible to completely eliminate the additional pressure. In this regard, the option of creating an underground floor was considered. In this case, the weight of the selected from the excavation soil compensates the load from the building. The required depth of the basement floor was determined analytically, calculations were performed in characteristic sections on 2D models, and the operation of all structures in combination was considered on a general 3D model. Based on the results of the study, a rational algorithm was proposed for calculating the additional pressure from ground construction on underground subway structures.