粘性土层井孔抽水试验的参数识别  

Identification of hydraulic parameters with slug test in clay soils

作　　者：杨利超[1] 王旭升[1] 焦赳赳[2] 王亚[2] 匡星星[2] 

机构地区：[1]中国地质大学水资源与环境学院,北京100083 [2]香港大学地球科学系

出　　处：《工程勘察》2011年第6期32-35,41,共5页Geotechnical Investigation & Surveying

基　　金：香港研究资助局科研项目(HKU702707P;HKU703109P)

摘　　要：粘性土层属于弱透水层,其水流、溶质运移和地球化学过程对于水文地质条件和环境变化具有重要意义。通过抽水试验来获取粘性土原位水力学参数是对粘性土水文地质问题进行研究的必要手段,但由于其渗透性很小,不能采用和常规含水层一样的方法求参。粘性土中的单孔抽水试验与一般含水层中的微水试验具有较大的相似性,因此可以借用微水试验的计算公式求参。本文以珠江三角洲淤泥质粘土井孔抽水试验为例,采用微水试验分析中的影响半径法和精确解法两种方法进行参数识别,获得了粘性土渗透系数和贮水率的参考值。Clay soils belong to aquitards in hydrogeology.Groundwater flow,solute transport and geochemical process within clay soils play important roles in hydrological conditions and environmental changes.It is necessary to obtain the in-situ hydraulic parameters in clay soils with pumping tests when the hydrogeological problems in clay soils are investigated.However,due to weak permeability of clay soils,the analysis method of the pumping test in clay is different from those applied for pumping tests in aquifers.It is indicated that single-well pumping test in clay soils is similar to slug test in aquifers.This similarity suggests that the parameter estimation method of a slug test can be applied in pumping test in clay soils.In this study,the equation using the radius of influence and the exact analytical solution of pumping test are applied in identifying hydraulic parameters of the clayed silt in Pearl river delta with pumping test data in boreholes.Hydraulic conductivity and specific storage of this silt are estimated and the efficiency of the method is discussed.

关 键 词：粘性土 抽水试验 微水试验 渗透系数 珠江三角洲 

分 类 号：P641.73[天文地球—地质矿产勘探]