（1 中国地质大学（北京）工程技术学院， 北京 100083； 

2 国土资源部深部地质钻探技术重点实验室， 北京 100083; 

3 万达集团项目管理中心， 北京 100022）

［摘要］膨胀土遇水发生软化，导致土体强度降低，降雨入渗对膨胀土路堑边坡影响较大。依据岩土饱和/非饱和渗流理论，利用有限元数值模拟分析软件，通过降雨入渗模型分析，建立膨胀土路堑边坡饱和/非饱和降雨入渗模型，模拟了降雨过程中边坡地下水含水率、压力水头变化规律，分析研究降雨入渗对路堑边坡渗流场及稳定性的影响规律。结果表明：降雨入渗对膨胀土边坡渗透影响仅发生在浅部区域，坡面低渗透性影响雨水入渗效果，裂隙性坡面则入渗稍快；对于低透水性、高基质吸力，短期降雨不至于导致边坡大面积滑塌破坏，边坡滑面只出现在表层，表现为浅层滑动，对深部土体影响不大。为以后膨胀土路堑边坡施工与防护提供一定的理论依据和数据参考。

［关键词］降雨入渗； 膨胀土； 路堑边坡； 有限元

中图分类号： TU443 文献标识码： A文章编号：  1002-848X(2016)S1-0851-05

Effects of rainfall and infiltration on the stability of expansive soil cutting slope

Wu Bohong1,2, Mo Jiang3

（1 School of Engineering and Technology, China University of Geosciences, Beijing 100083, China;

2 Key laboratory on Deep Geo-Drilling Technology of the Ministry of Land and Resources, China University of Geosciences, 

Beijing 100083, China; 3 Project Management Center, Wan Da Group, Beijing 100022, China)

Abstract: The expansive soil infiltrated with water resulting in reduced soil strength, which has greater impact on the stability of expansive soil cutting slope. Accodring to the rainfall infiltration model based on the geotechnical unsaturated/saturated seepage theory, the expansive soil cutting slope rainfall infiltration model was established by a finite element numerical simulation software, and the groundwater moisture content during the rainfall, pressure head variation, seepage field and stability effects by rainfall and infiltration were all studied. The results show that effects of rainfall and infiltration only occur in shallow areas. The infiltration was influenced by the low permeability of slope, while the fissured slope has large infiltration. For low permeability, high matric suction, short-term rainfall does not lead to a large area of slope slump destruction. Slope slip surface only in the surface layer, the performance of shallow slide, not for deep soil affected. Results from this paper provide a theoretical basis and reference data for future expansive soil slope construction and protection.

Keywords: rainfall; expansive soil; cutting slope; finite element

作者简介： 吴波鸿，博士，工程师。