基于统一强度理论的地基极限承载力公式

现有的地基临塑荷载及极限承载力公式均以Mohr-Coulomb强度理论为基础建立的，没有考虑中间主应力的效应，其计算结果一般偏小，没有充分发挥土体强度潜能。基于统一强度理论考虑中间主应力的影响，以Terzaghi公式的假设与原理为基础，导出地基极限承载力公式的一般形式，太沙基地基极限承载力公式是其特例。由于考虑中间主应力的影响，计算的地基承载力比太沙基地基极限承载力要大，可发挥土体的强度潜能，得到一系列的解答。

Formula of ultimate bearing capacity of shallow foundation based on unified strength theory

Based on Mohr-Coulomb strength theory, the effect of intermediate principal stress is ignored by the critical pressure and the formula of ultimate bearing capacity of shallow foundation, so its results are usually smaller than real values and that the potential of soil’s strength is not fully utilized. From unified strength theory that considers the effect of intermediate principal stress, the common formula of ultimate bearing capacity of foundation was deduced and the unified solutions was obtained. The formula of Terzaghi ultimate bearing capacity of foundation is the specific case of the unified formula. Through changing parameter of unified strength theory, a series of solutions can be obtained. The results indicate that bearing capacity of foundation is greater than Terzaghi ultimate bearing capacity of foundation because of the effect of intermediate principal stress.