含软弱土层边坡失稳机制与稳定性分析  

Instability Mechanism and Stability Analysis of Slope with Weak Soil Layer

作　　者：罗冰[1] 曾超[1] 何先志[1] 罗红明[2] 曹景超 LUO Bing;ZENG Chao;HE Xianzhi;LUO Hongming;CAO Jingchao(CCCC Second Highway Consultants Co.,Ltd.,Wuhan 430056,China;Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,State Key Laboratory of Geomechanics and Geotechnical Engineering,Wuhan 430071,China;Hualu Branch of Guangdong Road&Bridge Construction Development Co.,Ltd.,Meizhou 514400,Guangdong,China)

机构地区：[1]中交第二公路勘察设计研究院有限公司,武汉430056 [2]中国科学院武汉岩土力学研究所,岩土力学与工程国家重点实验室,武汉430071 [3]广东省路桥建设发展有限公司华陆分公司,广东梅州514400

出　　处：《路基工程》2024年第6期113-119,共7页Subgrade Engineering

基　　金：国家自然科学基金项目资助(42077270);贵州省交通运输厅科技项目(2022-122-016);中交第二公路勘察设计研究院有限公司科技研发项目(KDGZ-2018-004)。

摘　　要：采用有限元强度折减法和刚体极限平衡法,研究某含软弱土层边坡的失稳机制和稳定性,分析软弱土层对边坡失稳模式及稳定性的影响。结果表明:随着边坡中软弱土层的强度逐渐减小,边坡稳定性随之降低;当软弱土层强度分别大于、小于0.6倍周围土体强度时,边坡分别为圆弧形失稳机制、折线形失稳机制;采用刚体极限平衡法进行稳定性分析时,若边坡软弱土层与周围土层性质差异较大时应先分析边坡的失稳机制,然后进行边坡稳定性分析;采用有限元强度折减法时无须事先分析边坡失稳机制,相比刚体极限平衡法优势明显。以某二级公路含软弱土层边坡为例,采用折线形滑动计算方法对其稳定性进行分析,并采用有限元强度折减法进行验证。by using the finite element strength reduction method and the rigid body limit equilibrium method,the instability mechanism and stability of a slope with soft soil layer were studied,and the influence of soft soil layer on the instability mode and stability of the slope was analyzed.The result shows that,with the decrease of the strength of the weak soil layer in the slope,the stability of the slope is on the decline.When the strength of the soft soil layer is greater than or less than 0.6 times the strength of the surrounding soil,the slope is the circular arc instability mechanism and the broken line instability mechanism,respectively.When the rigid body limit equilibrium method is used for stability analysis,if the properties of the weak soil layer and the surrounding soil layer are quite different,the instability mechanism of the slope shall be analyzed,and followed by the slope stability analysis.The finite element strength reduction method does not need to analyze the instability mechanism of the slope in advance,and has obvious advantages over the rigid body limit equilibrium method.Taking the slope with soft soil layer of a secondary highway as an example,the stability of the slope is analyzed by the broken line sliding calculation method,and verified by the finite element strength reduction method.

关 键 词：软弱土层 边坡稳定性 有限元强度折减法 极限平衡法 变形破坏机制 

分 类 号：U416.14[交通运输工程—道路与铁道工程]