地基承载力确定的一种方法

根据三轴和直剪试验的特点并以Mohr强度理论为基础建立了Mohr包线的曲线形式。基于弹性理论导出了条形地基在均布荷载作用下塑性区方程，根据方程可以确定临塑荷载及塑性区的范围。与基于直线型Mohr-Coulomb准则建立起来的塑性区方程相比，该方程能反映土体抗剪强度增长随正应力增加逐渐趋缓的特点。算例分析表明：按两种方法计算得出的临塑荷载相差不大，塑性区连成一片时的荷载也基本一致；两种方法得出的塑性区的形状极为相似；随荷载增加，塑性区向下发展的速度比按传统方法得出的结果稍慢。

A Method to Determine Subgrade Bearing Capacity

No linear qualities of triaxiat tests results and direct shear tests results encourage a proper curve to be constructed to illustrate soils＇ limit equilibrium state based on Mohr envelope. With the application of elastic theory, equations are derived to calculate plastic range of ground under band-load operation, and then, critical load and plastic zone can be obtained. Several conclusions on the shape and size of plastic zone induced by band-load can be got after the comparison, which is performed between results respectively from the two methods. Even the difference between the shape and the size of the two kinds of plastic zone created by the same load is small and the two critical loads have the similar character, plastic zone increment with increasing upper load is quicker when the proposed method is applied.