降雨入渗对煤系膨胀土边坡瞬态稳定性影响分析  

Influence of rainfall infiltration on transient stability of expansive soil slope of coal measures

作　　者：廖炜 习明星 崔猛[1] 凌浚菠 张鸿[1] LIAO Wei;XI Mingxing;CUI Meng;LIN Junbo;ZHANG Hong(School of Civil and Architectural Engineering, Nanchang Institute of Technology,Nanchang 330099,China;Jiangxi Communication Consultation Company,Nanchang 330008,China)

机构地区：[1]南昌工程学院土木与建筑工程学院,江西南昌330099 [2]江西交通咨询有限公司,江西南昌330008

出　　处：《南昌工程学院学报》2019年第3期36-40,共5页Journal of Nanchang Institute of Technology

基　　金：国家自然科学基金资助项目(51609114);江西省教育厅科学技术研究项目(GJJ161101);南昌市优势科技创新团队项目(2017CXTD012);南昌工程学院研究生创新基金项目(YJSCX20180018)

摘　　要：采用非饱和瞬态渗流有限元与极限平衡法相结合,对降雨入渗过程中煤系膨胀土边坡的渗流场与稳定场进行数值模拟,分析了土体渗透系数、降雨强度、降雨持时以及坡比等参数变化对煤系膨胀土边坡稳定性的影响。研究结果表明,土体渗透系数对边坡安全系数有较大影响,渗透系数较大的边坡在降雨48 h后,其安全系数出现陡降,最大降幅达到27. 82%。降雨强度越大,相同降雨持时的边坡安全系数越小,安全系数的降幅也越大。坡比对煤系膨胀土边坡的安全系数有显著影响,边坡安全系数随着坡比的减小而增大,在降雨强度为8. 33×10^-7m/s的情况下,建议该类型土质边坡的坡比取值为1∶1. 5~1∶1.75。The seepage field and stability field of the expansive soil slope of coal measures in the process of rainfall infiltration were simulated by using unsaturated transient seepage finite element method and limit equilibrium method. On this basis the influence of soil permeability coefficient,rainfall intensity,rainfall duration and slope ratio on the stability of expansive soil slope in coal measures were analyzed. The results show that the soil permeability coefficient has a great impact on the slope safety coefficient,and the slope with a large permeability coefficient decreases sharply in the safety coefficient after 48 hours of rainfall,with the maximum decrease of 27. 82%. Under the same rainfall duration,the slope safety factor decreases with the increase of rainfall intensity. When the rainfall intensity increases,the slope safety factor decreases more. The slope ratio has a significant impact on the safety coefficient of the expansive soil slope of coal measures. The safety coefficient of the slope increases with the decrease of the slope ratio. When the rainfall intensity is 8. 33 × 10^-7 m/s,it is suggested that the slope ratio of this type of soil slope should be 1∶1.5 ~ 1∶1.7.

关 键 词：煤系地层 膨胀土边坡 降雨入渗 稳定性分析 瞬态渗流有限元 

分 类 号：U416[交通运输工程—道路与铁道工程]