摘要
随着黄土地区工业化和城镇化的不断发展,工业废水和生活污水中酸、碱以及pH值发生改变的雨水对土壤的污染问题日渐突出,地基土体受污染后在地表建筑物荷载的作用下会发生不同程度的二次沉降次生灾害。为研究酸碱污染对Q3黄土在不同压力区间内压缩指标的变化特征,对经过不同浓度污染后的土样进行标准固结试验。试验结果表明,对比孔隙水为蒸馏水的工况,酸污染土的总变形量增大,且最大压缩变形压力段下降;碱污染土的总变形量减小,且最大压缩变形压力段上升;土样经过酸污染后压缩系数增大,中压缩性变为高压缩性,但碱污染后的压缩系数却有不同程度的降低;酸污染土的压缩系数、压缩模量、体积压缩系数和压缩指数等压缩指标在小于400 kPa的中、低压力区间更敏感,碱污染土在大于400kPa的高压力区更敏感。在该基础上对侧限条件下的应力-应变关系进行分析,发现在不同污染情况下污染黄土的应力-应变曲线较好的符合Guanry关系。
With the development of industrialization and urbanization in loess regions,the problem of soil pollution caused by acid,alkali solutions in industrial wastewater,domestic sewage and rainwater with changed p H value is becoming more and more serious.Secondary disasters such as secondary subsidence may occur to different degrees under the load of surface buildings after the foundation soil is polluted.In order to find out the influence of acid-base pollution on the compression index at different pressure zones of Q3 loess,consolidation tests were carried out on intact loess samples contaminated by different concentrations of solutions.The results show that comparing the distilled water,the total deformation of acid-contaminated soil increases and the pressure section of the maximum deformation decreases;the total deformation of alkali-contaminated soil decreases and the pressure section of the maximum deformation increases.The compressibility of soil samples will change from medium to high compressibility with the increase of compressibility coefficient after acid solution contamination,but the compressive coefficient of alkali contaminated soil reduces somewhat.Compression coefficient,compression modulus,and volumetric compression coefficient of acid contaminated samples are more sensitive in medium and low pressure range less than 400 kPa,while those of the alkali contaminated samples are more sensitive under the high pressure range beyond 400 kPa.On this basis,the stress-strain relationship under confining condition is analyzed.It is found that the stress-strain curve of contaminated loess under different contamination conditions is in good agreement with the Guanry relationship.
作者
刘华
张硕成
牛富俊
邵珠山
牛泽林
鲁洁
LIU Hua;ZHANG Shuo-cheng;NIU Fu-jun;SHAOZhu-shan;NIU Ze-lin;LUJie(School of Civil Engineering,Xi’an University ofArchitecture and Technology,Xi’an,Shaanxi710055,China;State Key Laboratory of Frozen SoilEngineering,Northwest Institute of Eco-Environment and Resources,ChineseAcademy of Sciences,Lanzhou,Gansu730000,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2019年第A01期210-216,共7页
Rock and Soil Mechanics
基金
国家自然科学基金项目（No.51608436）
陕西省自然科学基础研究计划（No.2018JQ5003,No.2018JM5153）~~
关键词
Q3黄土
酸碱污染
压力敏感区间
压缩指标
Q3 loess
acid and alkali contamination
pressure sensitive section
compression index
