文献类型：期刊文献

中文题名：黄土–碎石毛细阻滞覆盖层储水能力实测与分析

英文题名：Field tests on water storage capacity of loess-gravel capillary barrier covers

作者：焦卫国 詹良通 季永新 贺明卫 刘振男

第一作者：焦卫国

通信作者：Jiao, Wei-Guo|[14440115d1579e19849a1]焦卫国;

机构：[1]贵州理工学院土木工程学院,贵州贵阳550003;[2]浙江大学软弱土与环境土工教育部重点实验室,浙江杭州310058;[3]贵州中建建筑科研设计院有限公司,贵州贵阳550006

第一机构：贵州理工学院土木工程学院

通信机构：School of Civil Engineering, Guizhou Institute of Technology, Guiyang, 550003, China|贵州理工学院土木工程学院;贵州理工学院;

年份：2019

卷号：41

期号：6

起止页码：1149-1157

中文期刊名：岩土工程学报

外文期刊名：Chinese Journal of Geotechnical Engineering

收录：CSTPCD;;EI(收录号：20193907468355);Scopus(收录号：2-s2.0-85072525076);北大核心:【北大核心2017】；CSCD:【CSCD2019_2020】；

基金：黔科合基础[2017]1079、[2017]1513-4;国家自然科学杰青基金项目(51625805);黔科合SY字[2015]3055,LH字[2016]7096;中建四局科技研发(CSCEC4B-2015-KT-03)

语种：中文

中文关键词：垃圾填埋场;覆盖层;毛细阻滞效应;有效储水能力;现场测试;极端降雨试验

外文关键词：landfill;cover;capillary-barrier effect;effective water storage capacity;field test;extreme rainfall experiment

摘要：中国西北地区气候较干旱,黄土分布广泛。就地取材采用当地的黄土作垃圾填埋场封场土质覆盖层具有技术可行性和良好的经济性。在西安江村沟垃圾填埋场建造了国内首个20m×30m大尺寸黄土–碎石毛细阻滞覆盖层现场试验基地,在基地开展了极端降雨试验。水量分配测试结果表明:总降雨量214.8 mm;坡面径流1.7 mm,占总降雨量的0.8%;土层存储(含蒸发)199.57 mm,占总降雨量的92.9%;渗漏13.53 mm,占降雨量的6.3%。基质吸力与水份运移规律分析结果表明:持续降雨条件下毛细阻滞覆盖层(900 mm)细粒土中表层土(15 cm深度以上)和底层土(85cm深度以下)的孔压(或体积含水率)均较高;底层土孔压(或体积含水率)较高是由于碎石–黄土界面间毛细阻滞效应对水份下渗的阻滞作用,这是有别于单一土层降雨入渗水份运移的显著特征。储水能力评估结果表明:极端降雨试验实测黄土–碎石毛细阻滞覆盖层有效储水量为251.95 mm。采用室内吸湿土水特征曲线评估覆盖层有效储水能力,有效储水量理论值Sfac为218.75 mm,实测值较理论值大15.18%,结果偏于安全。采用现场吸湿土水特征曲线评估覆盖层有效储水能力,有效储水量理论值Sfac为278.32 mm,实测值比理论值小9.47%,偏于危险。防渗设计中建议采用室内吸湿土水特征曲线。
The climate in northwest China is arid and the loess which is technically feasible and economical used for soil cover in landfills is widely distributed. At Jiangchungou Landfill, Xi’an, the first large size loess-grass capillary barrier cover 20 m×30 m is built, and the extreme rainfall experiments are carried out. The results of water distribution tests show that: with 214.8 mm rainfall, the slope runoff is 1.7 mm, accounting for 0.8% of the total rainfall, and the storage of soil(containing evaporation) is 199.57 mm, accounting for 92.9% of the total rainfall, and the leakage is 11.53 mm, accounting for 6.3% of the rainfall. The analysis of matrix suction and water migration shows that: with continuous rainfall, the pore pressure(or volume water content) of the surface soil(above depth of 15 cm) and the bottom soil(below depth of 85 cm) in the capillary-barrier cover are all high. The high pore pressure(or volumetric water content) of the underlying soil is due to the capillary-barrier effects at the gravel-loess interface, which is the distinct feature of rainfall infiltration water movement different from that of single soil layer. The evaluation of water storage capacity shows that: the effective water storage capacity of the loess-grass cover is 251.95 mm, measured by the rainfall experiments. The theoretical value of the effective water storage Sfac is 218.75 mm, evaluated by the indoor hygroscopic soil-water characteristic curve. The measured value is 15.18% larger than the the theoretical one, and the results are safe. The theoretical value of the effective water storage Sfac is 278.32 mm, evaluated by the field hygroscopic soil-water characteristic curve. The measured value is 9.47%, smaller than the theoretical one, and the results are dangerous. It is suggested that the indoor hygroscopic soil-water characteristiccurve should be adopted in anti-seepage design.