斜坡软弱路基稳定性分析的修正瑞典条分法  

Modified Swedish Slice Method for Stability Analysis of Weak Subgrade on Slope

作　　者：王春燕 洪宝宁[1,2,3] 单浩[1,2,3] 刘鑫 WANG Chunyan;HONG Baoning;SHAN Hao;LIU Xin(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;Jiangsu Research Center for Geotechnical Engineering Technology,Hohai University,Nanjing 210098,China;Geotechnical Research Institute,Hohai University,Nanjing 210098,China;Research Institute of Tunnel and Underground Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]河海大学江苏省岩土工程技术工程研究中心,江苏南京210098 [3]河海大学岩土工程科学研究所,江苏南京210098 [4]河海大学隧道与地下工程研究所,江苏南京210098

出　　处：《防灾减灾工程学报》2021年第6期1358-1365,共8页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金青年基金(51609071);中央高校基本科研业务费项目(2018B13714)资助。

摘　　要：斜坡软弱路基的滑塌形式与水平软弱路基相比,具有明显的易滑动性和非对称性。为了反映斜坡软弱路基与水平软弱路基失稳机理的区别,对两种路基形式进行离心机试验,证实了斜坡软弱路基的失稳的非对称性,因此在稳定性分析中要考虑势能差和非对称的影响。为了提高条分法在斜坡软弱路基稳定性计算的准确性,提出一种考虑不同倾斜角影响的修正瑞典条分法,引入反映势能差影响的"影响力"和反映滑动体外路堤填土重量的"附加力"。将瑞典条分法、修正瑞典条分法与有限元强度折减法对工程实例的计算结果比较分析,结果表明:(1)在稳定性分析中,斜坡软弱路基需要考虑势能差和非对称的影响;(2)"附加力"在各土条上的分布形式进行简化后,其计算结果与采用强度折减法进行的有限元计算结果较为接近;(3)按瑞典条分法计算出的安全系数比修正瑞典条分法偏大53.5%、比有限元强度折减法偏大50.5%,而修正瑞典条分法与有限元强度折减法计算结果只相差不足2%。Compared with horizontal weak subgrade,the weak subgrade on slope is easy to slide and the failure form is always asymmetrical. In order to reflect the difference between the weak subgrades on slope and horizontal ground,centrifuge test was carried out on the two subgrade forms. According to the test results,asymmetrical failure of the weak subgrade on slope is confirmed,so the influence of potential energy difference and asymmetry should be considered in the stability analysis. In order to improve the calculation accuracy on stability analysis of the weak subgrade on slope,a modified Swedish slice method is proposed to consider the influence of different inclination angles,and the "influencing load" reflecting the influence of the potential energy difference and the "additional load" reflecting the weight of the embankment outside the sliding body are introduced to analyze the stability of the weak subgrade. The results obtained by the Swedish slice method,the modified Swedish strip method and the finite element strength reduction method are compared and analyzed for an engineering exam-ple. The results show that:(1)the potential energy difference and asymmetry should be considered in the stability analysis of weak subgrade on slope;(2)After the distribution of the "additional load" on each soil slice is simplified,the calculation result is close to the finite element calculation result by the strength reduction method;(3)the safety factor calculated by the Swedish slice method is 53.5% larger than that by the modified Swedish strip method and 50.5% larger than that by the finite element strength reduction method,while the difference between the modified Swedish slice method and the finite element strength reduction method is less than 2%.

关 键 词：斜坡软弱路基 稳定性分析 影响力 附加力 修正瑞典条分法 

分 类 号：U416.1[交通运输工程—道路与铁道工程]