失稳状态下土坡稳定分析的改进条分法

An Improved Slice Method for Slope Stability Analysis Under Instable Condition

圆弧条分法是土坡稳定性分析的常用方法之一,但该法以假定各土条稳定性相等且与整个土坡相等为基础,属于不严密的刚体极限平衡法,存在一定的不合理性。以简单土坡为研究模型,运用改进条分法,研究了土坡失稳且土条间稳定性不等时,各土条间的传力特点、滑动规律及加速度协调条件;推导出了土坡失稳情况下,计算条间力大小及各土条稳定系数的理论公式。算例验证表明,这种方法不仅能准确分析整个土坡的稳定性,而且揭示了土坡内局部土条的稳定状态,对于实际施工具有重要参考价值。

The circular slice method is one of the normal methods for analyzing slope stability, which assumes that the stabilities of individual slices are equal and equaled to that of whole slope and belongs to an imprecise limit equilibrium method of rigid body with some irrationality. In this study, a simple slope was used as a model to study the features of force transferring between individual slices, discipline of slippage and compatibility condition of acceleration with improved slice method when the slope is in destabilization and the stabilities of individual slices are not equal. A theoretical formula for calculating interaction forces and the stable coefficient of individual slices under instable states was then deduced. The calculation of practical sample demonstrates that this method can be used to analyze accurately the stability of whole slope, as well as to reveal the stabl~ circumstance of part slices within a slope. It maybe possesses some important referential values for practical construction.