非饱和土边坡抗剪强度的力学参数影响及灵敏度分析

刘子振^{1, 2, 3}，言志信^{1, 2}，凌松耀⁴，任志华^{1, 2}，段建^{1, 2}

(1. 兰州大学 西部灾害与环境力学教育部重点实验室，甘肃 兰州，730000；
2. 兰州大学 土木工程与力学学院，甘肃 兰州，730000；
3. 台州学院 建筑工程学院，浙江 台州，318000；
4. 东盟营造工程有限公司，陕西 西安，710119)

摘 要：运用非饱和土的双应力变量理论，采用强度折减法详细分析土体各参数对边坡安全系数的影响，并通过灵敏度分析各参数对安全系数的影响。工程算例结果表明：各参数的变化对边坡安全系数的影响基本呈线性规律，其中土体含水率对安全系数影响线最显著；含水率、黏聚力和内摩擦角是非饱和土边坡稳定性分析的重要物理力学参数，为降雨条件下非饱和土边坡加固设计参数选取提供了依据。

关键词：非饱和土边坡；抗剪强度；含水率；安全系数；灵敏度

Sensitivity analysis and influence of mechanical parameters on shear strength of unsaturated soil slope

LIU Zi-zhen^{1, 2, 3}, YAN Zhi-xin^{1, 2}, LING Song-yao⁴, REN Zhi-hua^{1, 2}, DUAN Jian^{1, 2}

(1. Key Laboratory of Mechanics on Disaster and Environment in Western China of Ministry of Education,
Lanzhou University, Lanzhou 730000, China;
2. School of Civil Engineering and Mechanics, Lanzhou University, Lanzhou 730000, China;
3. School of Civil Engineering and Architecture, Taizhou University, Taizhou 318000, China;
4. Eastern Alliance Construction Engineering Co. Ltd., Xi’an, 710119, China)

Abstract:On the basis of the double-stress invariant theory of unsaturated soil, the influence of soil parameters on safety factor was analyzed with strength reduction methods. Then the impact of soil parameters on safety factor was analyzed by calculating sensitivity. The calculation results show that the linear relationship can be obtained between safety factor and soil parameters. And the most significant factor of influence on safety factor is the moisture content. Moisture content, cohesion and angle of friction are designated as some important physical and mechanical parameters of unsaturated soil slope. The result can provide the basis for selecting parameters of slope reinforcement during rainfall infiltration.

Key words:unsaturated soil slope; shear strength; moisture content; safety factor; sensitivity