基于强度双折减理论的粉土边坡稳定性研究  

Study on the Stability of Silt Slope Based on Strength Double Reduction Theory

作　　者：孙玉琢 李明宝[1] SUN Yuzhuo;LI Mingbao(College of Civil Engineering,Northeast Forestry University,Harbin 150040,Helongjiang,China)

机构地区：[1]东北林业大学土木工程学院,黑龙江哈尔滨150040

出　　处：《水力发电》2021年第3期19-24,共6页Water Power

基　　金：中央高校创新团队持续发展专项基金(2572017ET04);哈尔滨市优秀学科带头人基金(2013RFXXJ033)。

摘　　要：通过标准直剪试验结果,分析干湿循环对粉土强度指标的影响,提出粉土强度随干湿循环次数变化的关系式以及符合粉土边坡实际强度变化的安全系数计算方法,在此基础上建立ANSYS边坡模型分析粉土边坡的稳定性。研究表明,随着干湿循环次数的增加,重塑粉土的强度指标黏聚力和内摩擦角是以不同速率进行折减的,黏聚力折减幅度达30%,内摩擦角折减了12%;双折减方法所得到的安全系数小于传统折减方法,说明传统折减方法的计算结果偏安全,强度双折减方法更加符合实际。The influences of wetting-drying cycles on the strength index of silt are analyzed based on the standard direct shear test results,and the relationship between the strength of silt and the times of dry-wet cycles and the calculation method of safety factor in line with actual strength change of silt slopes are proposed.Based on this,the ANSYS slope model is established to analyze the stability of silt slope.The research shows that,(a)with the increase of the times of wetting-drying cycles,the cohesive force and internal friction angle of remodeled silt are reduced at different rates,and the cohesive force is reduced by 30%and the internal friction angle is reduced by 12%;and(b)the safety factor obtained by the strength double reduction method is smaller than that of the traditional strength reduction method,indicating that the calculation result of the traditional strength reduction method has excessive safety margin,and the strength double reduction method is more realistic.

关 键 词：土工试验 重塑粉土 干湿循环 强度双折减 有限元分析 

分 类 号：TU432[建筑科学—岩土工程]