水泥-硅粉改性膨胀土的性能研究  

Study on the Properties of Expansive Soil Modified by Cement and Silica Fume

作　　者：马露 徐晓阳 MA Lu;XU Xiao-yang(Collage of Architecture,Anhui Science and Technology University,Bengbu 233100,China)

机构地区：[1]安徽科技学院建筑学院,安徽蚌埠233100

出　　处：《辽宁科技学院学报》2020年第6期7-10,44,共5页Journal of Liaoning Institute of Science and Technology

基　　金：安徽省级质量工程课程类(智慧课堂)建设项目“画法几何与建筑制图”(2018zhkt175);安徽省教育厅高校自然科学重点研究项目“天然气水合物对含钙质砂无黏性土压缩与渗透特性的影响研究”(KJ2020A0080);安徽省教育厅高校自然科学重点研究项目“高含水率污泥真空快速脱水特性及机理研究”(KJ2018A0539)。

摘　　要：膨胀土在工程中表现出高膨胀、收缩和开裂的特性,会显著影响建筑地基的稳定性。以合肥地区中膨胀土为研究对象,水泥和硅粉作为改性材料,研究改性膨胀土的干缩特性。试验结果表明:水泥可以显著改善膨胀土的干缩性,水泥含量为12%时,试样总收缩量从22.3%降低到10.5%;总添加剂含量一定时,改性土的干缩性随硅粉增加而改善;水泥与硅粉按9:1质量比配制添加剂,改性效果较好;提出的改性膨胀土干缩模型的计算值与试验值吻合度较好,具有显著的实用性。Expansive soil tends to exhibit the characteristics of high expansion,shrinkage and cracking in the process of dry-wet cycling,and thus reduces the stability of building foundation.Using cement and silica fume as the modification materials,the drying shrinkage characteristics of the expansive soil in Hefei area were studied in this paper.The results showed that the shrinkage of expansive soil can be significantly optimized by cement.When the cement content is 12%,the shrinkage of samples decreases from 22.3%to 9.5%.When the total additive content is fixed,the dry shrinkage of the treated soil decreases by increasing the content of silica fume.The additive prepared by cement and silica fume at the mass ratio of 9:1 leads to a satisfied modification of expansive soil.The calculated values by the drying shrinkage model are in good agreement with the measured experimental data.Therefore,the model is of significant practicality.

关 键 词：非饱和膨胀土 干缩特性 水泥-硅粉 

分 类 号：TU443[建筑科学—岩土工程]