考虑地基土自重影响的地基承载力系数

Bearing capacity factors for foundations considering influence of soil weight

由于地基材料的非线性,采用传统的叠加法计算地基承载力会带来误差。基于无重土地基破坏模式的承载力系数不适用于考虑地基土重的情况,这是采用叠加法计算地基承载力会产生误差的主要原因。基于滑移线法,分析了由叠加法所带来误差的变化规律,并计算了能有效减小或完全消除该误差的承载力系数。研究表明:采用传统的叠加法计算得出的地基承载力是偏低的,且误差随地基土内摩擦角的增加而增加,随黏聚力的增加而减小。采用考虑土重影响的承载力系数计算地基承载力,能有效减小或完全消除叠加法所带来的误差。

Due to nonlinearity of ground material＇s behavior, the error will be induced using traditional superposition method to calculate bearing capacity. The main cause of superposition error is that the bearing capacity factors based on failure mechanism of weightless soil is not applicable for weight soil. Based on slip line method, variation trends of error induced by superposition method is analyzed; and bearing capacity factors which could reduce the error effectively or eliminate the error completely are calculated. The investigation results show that, bearing capacity calculated by traditional superposition method is conservative; the error increases with increasing of internal friction angle and decreases with increasing of cohesion. Error induced by superposition method will be reduced effectively or eliminated completely if bearing capacity factors considering soil weight.