高强粉质黏土-水泥搅拌土固化剂配比研究  

Study on Curing Agent Ratio of High Strength Silty Clay-Cement Mixed Soil

作　　者：刘银芳 胡椿华 秦金龙 童立红 朱碧堂 郭易盟 李志平[2] Liu Yinfang;Hu Chunhua;Qin Jinlong;Tong Lihong;Zhu Bitang;Guo Yimeng;Li Zhiping(Fujian Geotechnical Engineering Investigation and Research Institute Co.,Ltd.,Fuzhou 350001,China;Key Laboratory of Geotechnical Infrastructure Safety and Control of Jiangxi Province,East China Jiaotong University,Nanchang 330013,China;Nuclear Industry Eastern China Construction Engineering Group Co.,Ltd.,Nanchang 330013,China)

机构地区：[1]福建岩土工程勘察研究院有限公司,福建福州350001 [2]华东交通大学江西省地下空间技术开发工程研究中心,江西南昌330013 [3]核工业华东建设工程集团有限公司,江西南昌330013

出　　处：《华东交通大学学报》2023年第4期33-39,共7页Journal of East China Jiaotong University

基　　金：中国冶金地质总局2021年科研项目(CMGBK202102);江西省科技合作专项项目(20212BDH81034)。

摘　　要：为提高粉质黏土-水泥搅拌土强度,使其与钢筋或型钢共同作用形成水泥土搅拌墙。以南昌地区粉质黏土为例,在现有水泥土改良剂性能研究基础上,通过选择合适的固化剂,采用正交试验,对16组粉质黏土改良方案形成的搅拌土开展室内无侧限抗压强度试验和渗透试验,研究水泥、水玻璃、生石膏和生石灰不同配比对粉质黏土改良后强度性能的影响,并对试验结果进行了极差和方差分析。结果表明:对搅拌土的抗压强度影响程度从大到小依次为水泥掺量、水玻璃掺量、生石膏和生石灰掺量,确定粉质黏土固化改良的最优配比为水泥掺入比24%、水玻璃6%、生石膏2%、生石灰0、萘系减水剂1.5%,并推荐在水灰比为1.5、粉质黏土含水率为12%时使用。经过筛选固化剂和优化配比后,粉质黏土在标准龄期28 d时强度可以达到8.6 MPa。最后通过扫描电镜试验,对高强粉质黏土-水泥搅拌土的微观结构进行了分析,阐述了高强水泥搅拌土的产生机理。To improve the strength of silty clay-cement mixed soil,a cement-soil mixed wall is formed by making it work together with steel bars or sections.In this paper,taking the powdered clay soil in Nanchang area as an example,based on the existing research on the performance of cement soil improver,indoor unconfined compressive strength test and permeability test were conducted on the mixed soil formed by 16 groups of silty clay improvement schemes through selecting suitable curing agents and using orthogonal test to study the effects of different ratios of cement,water glass,gypsum and quicklime on the strength performance of the improved silty clay.The results were analyzed by the range analysis and variance analysis.The results showed that the compressive strength of the mixed soil was influenced by the amount of cement,water glass,gypsum and quicklime in descending order,and the optimal ratio of cement,water glass,gypsum,quicklime and naphthalene water reducing agent was determined to be 24%,6%,2%,0 and 1.5%,and was recommended to be used when the water-cement ratio was 1.5 and the moisture content of the silty clay was 12%.After screening the curing agent and optimizing the proportion,the strength of the silty clay could reach 8.6 MPa at the standard age of 28 d.Finally,the microstructure of the high-strength silty clay-cement mixed soil was analyzed by scanning electron microscope test,and the mechanism of the generation of high-strength cement mixed soil was elaborated.

关 键 词：粉质黏土 正交试验 水泥土 固化剂 无侧限抗压强度 微观结构 

分 类 号：TU472[建筑科学—结构工程]