粉煤灰堆场改性黄土衬里的渗透试验研究  

Permeability Performance of Modified Loess Soil Liner for Coal-Ash Storage Yard

作　　者：刘吉胜[1] 张虎元[1] 赵天宇[1] 严耿升[1] 

机构地区：[1]兰州大学西部灾害与环境力学教育部重点实验室,甘肃兰州730000

出　　处：《粉煤灰》2010年第5期27-31,共5页Coal Ash China

基　　金：国家自然科学基金项目(批准号50678075);中国建筑股份有限公司项目(CSCEC-2008-Z-21)

摘　　要：通过一系列渗透试验,研究了不同添加剂改性黄土的防渗性能。选用黏性较大的兰州黄土和砂性较大的榆林黄土两种代表性黄土为防渗衬里主料,分别向其中添加不同比例的膨润土、石灰、水泥和粉煤灰作为改性材料,进行渗透试验。结果表明,膨润土细颗粒充填于黄土颗粒大孔隙中,水化膨胀后减小了孔隙体积并且阻隔了孔隙间的贯通性,能有效降低改性衬里的渗透系数。石灰、水泥和粉煤灰在降低改性衬垫渗透系数方面作用不大,由于水化反应形成新的复合土颗粒骨架和网格骨架,反而会使渗透系数增大,不适合作为黄土改性衬里的改性材料。Based on research on impervious loess liner for coal-ash storage yard of in northwest region of China, loess mixed with certain proportion of modified materials can improve simply and effectively permeability. The permeability of loess modified with different admixtures was studied through a series of permeability test. Bentonite, lime or cement were mixed into Lanzhou loess soil and Yulin loess soil as modified liner for coal-ash storage yard. Test results shows that fine grains of bentonite which filled in macropore of loess grain expanded and cut off the macropore. The permeability of loess soil modified with bentonite improved gradually by increasing of bentonite ratio. The macropore of modified loess soil with lime, fly ash or cement got larger because of production of new soil skeleton in duration of hydration. So it is not unsuitable for them to be used as modified materials for liner.

关 键 词：改性黄土 膨润土 渗透系数 柔性壁渗透仪 

分 类 号：X705[环境科学与工程—环境工程] TU528.32[建筑科学—建筑技术科学]