Abstract:The influence depth of the additional stress in the buildings is an important basis for evaluating the stress balance of the newly built buildings in the coal mining subsidence area, and casuing "secondary settlement" of the broken rock mass. In this paper, the calculation principle of the influence of corner additional stress on the underground influence depth under the uniform load of rectangular foundation buildings has been introduced and analyzed. The method of linear approximation is used to transform complex and nonlinear soil weight stress function and building additional stress function into line segment infinitesimal, and then the influence depth of building additional stress can be obtained by calculating the intersection point of two straight lines. The computing program is completed by C# language. In the end, the relationship between the influence depth of the additional stress of the building and the bulk density of the soil (or rock), the load of the building, the area of the foundation and the shape of the foundation is analyzed through an engineering example.