细粗粒覆盖层对膨胀土边坡防渗效果数值研究  

Numerical study on anti-seepage effect of expansive soil slope treated by fine coarse grain cover layers

作　　者：权全 邱金伟 胡波[2] 李涛 刘明华 宋诚 吴昊 QUAN Quan;QIU Jinwei;HU Bo;LI Tao;LIU Minghua;SONG Cheng;WU Hao(Anhui Provincial Group Limited for Yangtze-to-Huaihe Water Diversion,Hefei 230000,China;Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources,Changjiang River Scientific Research Institute,Wuhan 430010,China;Anhui Survey and Design Institute of Water Resource and Hydropower Co.,Ltd.,Hefei 230000,China)

机构地区：[1]安徽省引江济淮集团有限公司,安徽合肥230000 [2]长江科学院岩土力学与工程重点实验室,湖北武汉430010 [3]安徽省水利水电勘测设计研究总院股份有限公司,安徽合肥230000

出　　处：《人民长江》2024年第7期221-228,共8页Yangtze River

基　　金：安徽省引江济淮集团有限公司科技项目(YJJH-ZT-ZX-20230118528,YJJH-ZT-ZX-20191031216);国家自然科学基金青年基金项目(52208329)。

摘　　要：为了研究由一层细粒土层下覆一层粗粒土层组成的毛细阻滞护坡结构对膨胀土边坡防渗效果的影响,采用初应变法将膨胀土中湿度应力以类似温度应力场的形式施加到土体上,通过数值软件实现对膨胀土边坡吸湿膨胀的数值模拟,将等效塑性应变完全贯通作为边坡稳定性的判别准则。数值模拟结果表明:毛细阻滞护坡结构层形成强透水层,能有效防止降雨入渗,达到较好的护坡效果;0.5 m厚细粒土层+0.2 m厚粗粒土层组成的毛细阻滞结构护坡效果与1.5 m水泥改性土护坡结构相当。毛细阻滞生态护坡结构对膨胀土边坡有较好的护坡效果。研究成果可以为相关膨胀土边坡防护提供理论和设计依据。This study investigates the anti-seepage effect of a capillary barrier consisting of a layer of fine-grained soil underlying and a layer of coarse-grained soil on expansive soil slopes through the numerical model.The moisture stress in expansive soil is applied to the soil in the form of a temperature stress field using the initial strain method,and the numerical simulation of hygroscopic expansion of expansive soil slope is realized by numerical software.The criterion for determining slope stability is whether the equivalent plastic strain zone is completely penetrated or not.The numerical simulation results indicate that the capillary barrier cover layer forming a strong permeable layer can effectively prevent rainfall infiltration and achieve a good slope protection effect.Under the selected operating conditions in this article,the slope protection effect of the capillary barrier cover layer composed of 0.5 m fine-grained soil layer and 0.2 m coarse-grained soil layer is equivalent to that of 1.5 m cement modified soil.The capillary blocking ecological slope protection structure has a good slope protection effect on expansive soil slopes.The research results can provide a theoretical and designed basis for related expansive soil slope protection.

关 键 词：粗粒土覆盖层 膨胀土边坡 毛细阻滞护坡结构 吸湿膨胀 数值模拟 防渗效果 

分 类 号：TU43[建筑科学—岩土工程]