考虑条间力合理性的不平衡推力法改进  

Improvement of Unbalanced Thrust Method Considering Rationality Of Inter Strip Force

作　　者：戴嘉宁 陈文胜 蒋茂林 李颖豪 Dai Jianing;Chen Wensheng;Jiang Maolin;Li Yinghao

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114

出　　处：《重庆建筑》2021年第11期40-44,共5页Chongqing Architecture

基　　金：国家自然科学基金“基于块体模型细胞自动机的节理岩质边坡稳定性和演化机制研究”(51778067)。

摘　　要：不平衡推力法是我国独创的一种边坡稳定性分析方法,因其计算简单,并且可以计算边坡推力而被广泛运用。但传统不平衡推力法的条间力物理意义不明确,是剩余下滑力的简单代替,在特殊工况下可能出现条间剪力超出抗剪强度的不合理现象,无法满足边坡合理性条件,并且安全系数误差较大,偏于不安全。极限平衡条分法模型是一个静不定模型,力的解答有无数种可能,而不平衡推力法只是其中一种。该文在不平衡推力法的基础上提出一种改进方法,该法根据整体性安全系数在边坡任一点都相同的原理,令条间剪力取得条间抗剪强度,并按照滑动面抗滑力相同的折减系数进行强度折减,确保条间力始终满足合理性条件。通过理论分析和人工算例计算表明:改进方法的计算过程物理意义明确,相较于传统不平衡推力法,在多种不同角度变化的滑动面计算结果误差更小,可求得更大的滑坡推力,能够为边坡加固提供更为准确有效的参考。Unbalanced thrust method is an original slope stability analysis method in China,and it is widely used due to its simple calculation and ability to calculate slope thrust.However,the inter-slice force in the traditional unbalanced thrust method has an obscure physical meaning,and it is a simple substitute for the residual sliding force.Under special conditions,the shear force between slices may exceed the shear strength,so it can not meet the reasonable conditions of the slope,with big errors in the safety factor.The limited equilibrium slice method model is a statically indeterminate model,and there are countless possibilities to solve the force,but the unbalanced thrust method is just one of them.Based on the unbalanced thrust method,this paper proposed an improved method.According to the principle that the integral safety factor is the same at any point of the slope,inter-slice shear obtains inter-slice strength,and the strength is reduced based on the same reduction factor to the sliding surface,so as to ensure that the inter-slice force always meets the reasonable conditions.The theoretical analysis and manual calculation showed that the improved method has clear physical meaning.Compared with the traditional unbalanced thrust method,this method causes smaller errors in calculation of the sliding surface with different angles,and obtains larger landslide thrust,which can provide more accurate and effective reference for slope reinforcement.

关 键 词：边坡 极限平衡条分法 不平衡推力法 条间力 改进方法 

分 类 号：TU43[建筑科学—岩土工程]