采煤塌陷区建筑物附加应力影响深度的计算与分析

Calculation and Analysis of Influence Depth of Additional Stress on Buildings in Coal Mining Subsidence Area

建筑物附加应力的影响深度是评价采空区新建建筑是否会破坏冒落带和导水裂隙带内的应力平衡状态,进而引发破碎岩体"二次沉降"的重要依据。该文介绍分析了矩形基底建筑在均布荷载作用下角点附加应力对地下影响深度的计算原理,提出了使用线性逼近的方法,分别将复杂、非线性的土层自重应力函数及建筑物附加应力函数转化为线段微元,通过计算两直线段交点来获得建筑物附加应力影响深度的方法,并使用C#语言编制了相关计算程序。结合工程实例,分析了建筑物附加应力影响深度与土(岩)层容重、建筑物荷载、地基面积、地基形状的关系。

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.