摘要
在正常固结黏土或弱超固结黏土边坡稳定性分析中,常常假设不排水抗剪强度cu随深度线性增加,而在水平方向上保持不变。然而,由于应力环境、沉积条件和风化作用等因素的影响,不排水抗剪强度可能同时沿着水平向变化。研究了不排水强度随深度线性增加,且沿水平向变化的边坡稳定性。引入强度变化倾角i来描述水平向强度变化特征。基于极限分析上限定理,给出了破坏机构内外功率计算公式,并求得稳定系数表达式。利用编程优化求得稳定系数的最优解答。探讨了抗剪强度空间变化特性对边坡稳定性和临界滑动面的影响。研究表明,当边坡坡度较缓,倾角i对于边坡稳定性影响较为显著;随着倾角i的增大,滑面深度逐渐增加。本文解答对于开挖边坡设计及施工具有一定的指导价值。
In the stability analysis of normally consolidated or lightly overconsolidated clays,it is often assumed that the undrained shear strength cu increases linearly with depth but remains constant in the horizontal direction.However,the shear strength may vary in the horizontal direction due to the stress condition,sedimentary condition and weathering process.In this paper,stability of slopes with undrained shear strength increasing linearly with depth and varying in the later extent are analyzed.The strength varying inclination i is introduced to describe the horizontal strength varying characteristics.Based on the upper bound theorem limit analysis,the formulas for the external and internal work rate are obtained,and then the stability number is obtained.The least upper bound solution of the stability number is obtained through the optimization procedure.The influence of spatial varying undrained shear strength on slope stability and the critical failure mechanism is discussed.The results show that when the slope is gentle,the inclination i has a significant impact on the slope stability.With the decrease of inclination i,the depth of the critical slip surface gradually increases.The solution obtained may provided practical guidance for the design and construction of excavations.
作者
杜静
DU Jing(Department of Construction Engineering,Guangxi Transport Vocational and Technical College,Nanning 530023,China)
出处
《结构工程师》
北大核心
2020年第4期156-161,共6页
Structural Engineers
基金
广西高校中青年教师基础能力提升项目(2018KY1022)。
