Stiffness influence in pit corner zones on the retaining walls movement in sandy soils

Engineering calculations in the spatial formulation, as well as the results of field observations, show a significant decrease in lateral displacements of the foundation pit retaining walls in the area of the corner zones. At the same time, in design practice, a large number of decisions are made on the basis of calculations in a flat formulation. For pits with a depth of more than 10 m, the influence of corner zones can make a significant contribution to the reduction of movements and, as a result, internal forces in the retaining walls and restraint systems. The underestimation of the corner effect leads to an increase of the retaining structures construction cost. 
This article presents the results of FEM calculations studies of the monolithic reinforced concrete wall functioning in the corner zones of pit in sandy soils. As a result, it was revealed that the movement of the diaphragm wall in the area of the corner zones of the foundation pit is influenced by such factors as: the pit depth, the angle between retaining walls, and the stiffness of the retaining wall and struts. At the same time, the properties of the sand and the stiffness of the retaining wall and struts do not affect the distribution of displacements in the corner zones.