按抗剪强度指标计算复合地基极限承载力的近似解

Approximate solution from shearing strength index-based calculation on ultimate bearing capacity of composite foundation

在竖向荷载作用下,假定地基滑动面为Prantle滑动面。利用极限平衡分析方法,导出了按增强体和基体的抗剪强度指标计算条形基础复合地基极限承载力的近似公式。在此基础上对分层地基、矩形基础和圆形基础复合地基极限承载力的计算方法进行了讨论。计算结果表明:按抗剪强度指标确定复合地基极限承载力方法与规范法所得结果基本一致,验证了该方法的适用性。该方法沿袭了天然地基极限承载力的计算方法,其计算参数容易获得,较之规范法便于工程师应用。

Under the vertical load, a foundation is supposed to be a Prantle＇ s sliding plane. In accordance with the limit equilibrium method, the approximate solution of the ultimate bearing capacity of a strip composite foundation from the calculations based on the shearing strength indexes of both the natural soil mass and the strengthened soil mass of the foundation is derived. On the basis of this, the method of the calculation on the ultimate bearing capacity of the foundation composed of the layered ground, rectangular foundation and circular foundation is discussed herein. The calculation result shows that the calculation result from the method of the shearing strength index-based calculation for the ultimate bearing capacity of composite foundation is basically con- sistent with that from the method specified in the specification concerned, and then the applicability of this method is justified as well. As following the calculation method for the calculation on the ultimate bearing capacity of natural ground, the parameters for this method are easy to be got, and furthermore, it is more convenient for the actual application than that given in the relevant specification.