北疆供水工程白砂岩地基的渗透性研究  

Permeability of White Sandstone Foundation in North Xinjiang Water Supply Project

作　　者：王永鹏 刘洪强 杨志勇 杨鹏年[2] 冯思阳 WANG Yong-peng;LIU Hong-qiang;YANG Zhi-yong

机构地区：[1]新疆水利发展投资集团,新疆乌鲁木齐830000 [2]新疆农业大学水利与土木工程学院,新疆乌鲁木齐830052

出　　处：《海河水利》2023年第7期86-89,共4页Haihe Water Resources

基　　金：国家自然科学基金项目:四维同化框架下荒漠河岸林蒸散与地下水互制机理解耦建模(U2003105)。

摘　　要：北疆供水工程的地基土层以含局部泥岩夹层的白砂岩地基为主,其水力特性关乎工程病害的形成与发育。以倒虹吸段白砂岩地基土为研究对象,分别取白砂岩和夹层泥岩土样,通过室内试验确定其渗透系数;并通过现场原位竖管试验测定白砂岩地基垂向与水平渗透系数对比。结果显示,室内试验确定的白砂岩与泥岩的工程分类分别为粉土质沙和低液限黏土,渗透系数分别为1.04×10^(-5)和5.87×10^(-7)m/s;现场竖管试验测定的白砂岩地基垂向渗透系数为5.40×10^(-7)m/s,水平为1.45×10^(-5)m/s,水平渗透系数是垂向的26.85倍;白砂岩地基垂向渗透系数取决于泥岩夹层,水平方向取决于白砂岩主层;白砂岩地基垂向渗透系数在数值上与泥岩十分接近,水平方向略大于白砂岩。白砂岩、泥岩中过高的细颗粒含量和较高的密实度使得白砂岩地基整体具有较差的渗透性,白砂岩地基沉积层的各向异性导致其不同方向渗透系数差异悬殊。The foundation soil layers in North Xinjiang Water Supply Project mainly consist of white sandstone with localized interbedded mudstone,and their hydraulic characteristics are crucial to the formation and development of engineering diseases.Taking the white sandstone foundation soil in the inverted siphon section as the research object,laboratory tests are conducted to determine the permeability coefficients of the white sandstone and interbedded mudstone samples.In-situ vertical tube tests were also carried out to compare the vertical and horizontal permeability coefficients of the white sandstone foundation.The results reveal that the engineering classification of the white sandstone and mudstone determined from the laboratory tests are silt-like sand and low liquid limit clay,with permeability coefficients of 1.04×10^(-5)m/s and 5.87×10^(-7)m/s,respectively.The in-situ vertical tube test determines a vertical permeability coefficient of 5.40×10^(-7)m/s and a horizontal permeability coefficient of 1.45×10^(-5)m/s for the white sandstone foundation.The horizontal permeability coefficient is approximately 26.85 times greater than the vertical coefficient.The vertical permeability coefficient of the white sandstone foundation is controlled by the mudstone interbeds,while the horizontal direction was influenced by the main white sandstone layer.The vertical permeability coefficient of the white sandstone foundation is numerically close to that of the mudstone,while the horizontal direction shows slightly higher permeability than the white sandstone.The high content of fine particles and compactness in both the white sandstone and mudstone contributes to the overall poor permeability of the white sandstone foundation.The anisotropy of the sedimentary layers in the white sandstone foundation results in significant differences in permeability coefficients in different directions.

关 键 词：白砂岩地基 粒径分析 竖管试验 各向异性 渗透系数 

分 类 号：TV223.1[水利工程—水工结构工程]