饱和-非饱和渗流作用下土质库岸路基稳定性分析  

Stability Analysis of Soil Reservoir Bank Subgrade under Saturation-Unsaturated Seepage

作　　者：陈龙飞 林棋文 邓安 何蕃民 王植 CHEN Longfei;LIN Qiwen;DENG An;HE Fanmin;WANG Zhi(Chengdu Surveying Geotechnical Research Institute Co.,Ltd.of MCC,Chengdu 610023,China;Faculty of Geosciences and Engineering,Southwest Jiaotong University,Chengdu 611756,China;Nuclear Industry Southwest Geotechnical Investigation&Design Institute Co.,Ltd.,Chengdu 610065,China)

机构地区：[1]中冶成都勘察研究总院有限公司,成都610023 [2]西南交通大学地球科学与环境工程学院,成都611756 [3]核工业西南勘察设计研究院有限公司,成都610065

出　　处：《路基工程》2024年第6期191-197,共7页Subgrade Engineering

基　　金：国家自然科学基金项目(U2244229)。

摘　　要：以四川省乐山市夹江县某典型土质库岸路基工程为例,分析库岸边坡的变形机制;基于饱和-非饱和渗流理论建立数值模型,研究天然、降雨和水位骤降工况下边坡渗流场、位移、等效塑性应变及稳定性,分析塌岸范围并提出工程治理建议措施。结果表明:天然工况下边坡稳定系数为1.15,处于基本稳定状态;降雨工况下边坡稳定系数为1.05,处于欠稳定状态;水库水位骤降工况下边坡变形范围扩大,剪出口出现在坡脚,边坡稳定系数为0.92,处于不稳定状态。采用“两段法”和“卡丘金公式法”预测塌岸宽度为8.8~9.5 m,建议采用“桩基托梁挡墙+排水”工程治理措施。Taking a typical subgrade project of soil reservoir bank in Jiajiang County,Leshan City,Sichuan Province as an example,the deformation mechanism of bank slope is analyzed.Based on the saturation-unsaturated seepage theory,a numerical model was established to study the seepage field,displacement,equivalent plastic strain and stability of the slope under natural,rainfall and water level sudden drop conditions.The scope of bank collapse was analyzed and the engineering treatment measures were proposed.The results show that the slope stability coefficient is 1.15 under natural conditions,which is basically stable.Under the condition of rainfall,the slope stability coefficient is 1.05,which is in the understable state.Under the condition of sudden drop of reservoir water level,the deformation range of the slope expands,the shear outlet appears at the slope foot,and the slope stability coefficient is 0.92,which is in an unstable state.The"two-stage method"and"Kachugin formula method"are used to predict the bank collapse width of 8.8-9.5 m,and it is recommended to adopt"pile joist retaining wall+drainage"engineering treatment measures.

关 键 词：土质库岸 变形破坏 边坡稳定性 孔隙水压力 渗流场 

分 类 号：P641.1[天文地球—地质矿产勘探]