摘要
压实度是道路、房建、水利等工程领域评价土体压实质量的重要参数,与土体含水率和电导率密切相关。而频域反射技术(frequency domain reflectometry,FDR)可用于快速测定土体含水率和电导率。首先利用频域反射技术分别对多种压实状态下红黏土、膨胀土和黄土的含水率、电导率进行测量;然后对含水率测值进行室内标定,得到3种土的含水率标定曲线;通过偏最小二乘回归分析方法(partial least squares regression,PLSR)建立了3种土体的压实度-含水率-电导率之间的经验关系,并与实测值进行了对比分析;再根据扫描电子显微镜(scanning electron microscopy,SEM)和压汞法(mercury intrusion porosimetry,MIP)试验结果分析了其微观机制;最后对拟合公式得到的压实度预测值进行随机试样验证,建立与实测值的误差评估体系,结果表明基于压实度-含水率-电导率之间的关系而提出的拟合公式预测压实度的精度较高。相关研究可为道路、房建、水利等工程中土体压实度的快速检测提供参考。
The compaction degree is an important parameter for evaluating the quality of soil compaction in many engineering constructions such as roads,housing construction,and water conservancy project,and it correlates with moisture content and electrical conductivity.Frequency domain reflectometry(FDR)can rapidly measure soil moisture content and electrical conductivity.Firstly,in this research,FDR was adopted to rapidly measure the values of soil moisture content and electrical conductivity regarding lateritic soil,expansive soil,and loess at varying compaction degrees.Secondly,the measured values of moisture content were calibrated in laboratory,and the calibration curves of the three soils were obtained accordingly.Thirdly,empirical relationships between compaction degree,moisture content and conductivity of the three soils were established using the partial least squares regression(PLSR)analysis method,and compared with the measured value.Fourthly,scanning electron microscopy(SEM)and mercury intrusion porosimetry(MIP)tests revealed its mechanism from microscopic aspect.Finally,the predicted value of the compaction degree obtained by the fitting equation was verified,and an error evaluation system was established.The results show that such fitting equations based on the relationship between compaction degree,moisture content,and electrical conductivity have a high prediction accuracy.Therefore,the results in this work can provide a good reference for the rapid detection of soil compaction in roads,housing construction,water conservancy and other projects.
作者
冉宇玲
柏巍
孔令伟
李雪梅
樊恒辉
杨秀娟
RAN Yu-ling;BAI Wei;KONG Ling-wei;LI Xue-mei;FAN Heng-hui;YANG Xiu-juan(State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;College of Water Resources and Architectural Engineering,Northwest Agriculture and Forestry University,Yangling,Shaanxi 712100,China;Zhejiang Institute of Hydraulics&Estuary,Hangzhou,Zhejiang 310020,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2023年第8期2458-2470,共13页
Rock and Soil Mechanics
基金
国家自然科学基金面上项目(No.41772339,No.41877281)。
关键词
压实度
频域反射
含水率
电导率
compaction degree
frequency domain reflectometry
moisture content
electrical conductivity
