基于突变特征的边坡双强度折减系数量化研究  

Quantitative research on two strength reduction factors of slope based on mutation characteristic

作　　者：苏永华[1] 李帅 方砚兵 SU Yong-hua;LI Shuai;FANG Yan-bing(School of Civil Engineering,Hunan University,Changsha 410082,China;Henan Provincial Communications Planning and Design Institute Co.,Ltd.,Zhengzhou 451450,China)

机构地区：[1]湖南大学土木工程学院,长沙410082 [2]河南省交通规划设计研究院股份有限公司,郑州451450

出　　处：《计算力学学报》2019年第3期375-382,共8页Chinese Journal of Computational Mechanics

基　　金：国家自然科学基金(51578232;51878266)资助项目

摘　　要：边坡失稳是一个由渐变演化至突变破坏的过程,过程中土体的强度参数c和φ发挥作用的路径和衰减程度不同。目前,双强度折减策略DRM在边坡稳定性评估中已逐渐形成共识,但双强度参数间的真实折减关系或折减关系的求解方法难以准确定义。以坡体抵抗外部环境能力最大值原理为依据,引入非线性分析突变理论,以坡体的极限承载力为考察量,建立其与双强度折减比的突变模型函数来考察边坡整体稳定性,进而量化折减过程中c和φ的折减比。结合算例,通过与已有方法的计算结果进行对比,验证了方法的合理性,并探究了c和φ以及坡度与折减比间的演化规律及机理。研究的执行思路可为双强度折减技术的探讨提供有益参考。Failure of a slope is a process of gradual evolution to mutational destruction.The shear strength parameters c andφhave different effect paths and decay rates during the destruction process.Currently,the double strength reduction technique has been widely accepted gradually in the field of slope stability evaluation,but the real relationship of reduction between c andφis difficult to define accurately.Based on the maximal principle of bearing capacity of a slope to external environment,mutation theory of nonlinear analysis is introduced.The ultimate bearing capacity of a slope is taken as the evaluation basis,the model function between the reduction ratio and the ultimate bearing capacity is built,and then,the reduction ratio of c andφis quantified.Utilizing a slope example,rationalization of the proposed method is verified according to comparison with some reported methods.Evolvement rule and mechanism between c andφas well as the slope angle and the reduction ratio are explored.The implementation idea of this research may provide helpful reference for discussion of double strength reduction technique.

关 键 词：边坡稳定性分析 双强度折减策略 突变理论 折减比 下限法 

分 类 号：TU43[建筑科学—岩土工程] O344.7[建筑科学—土工工程]