矿渣基地聚物流态盾构固化土的性能研究  

Performance of Slag-Based Geopolymer Flow Shield-Cured Soil

作　　者：牛家栋 杜运兴[1] 张自成 李艳秋 秦宝坤 NIU Jiadong;DU Yunxing;ZHANG Zicheng;LI Yanqiu;QIN Baokun(College of Civil Engineering,Hunan University,Changsha 410082,China;China Construction First Group the Fifth Construction Company,Beijing 100024,China)

机构地区：[1]湖南大学土木工程学院,长沙410082 [2]中建一局集团第五建筑有限公司,北京100024

出　　处：《硅酸盐通报》2024年第6期2176-2185,共10页Bulletin of the Chinese Ceramic Society

基　　金：长沙市科技计划重大专项(kq1804002)。

摘　　要：为实现对地下工程中的高含水率盾构土资源化利用,探究地聚物材料固化盾构土的可行性,本文采用矿渣基地聚物固化盾构土,通过研究碱激发剂模数、矿物配比、碱激发剂掺量、温度对不同种类盾构固化土无侧限抗压强度和工程性能的影响规律,确定固化土配合比设计,在此基础之上研究地聚物掺量对固化土水稳性的影响,并采用SEM对盾构固化土进行微观分析,揭示其固化机制。结果表明,在试验拟定的水固比下,两种不同土质流态盾构固化土均有良好的力学性能和工程性能,矿渣基地聚物产生了无定形凝胶,增强了土壤颗粒之间的胶结及密实度,其中固化剂掺量为干土质量22%的盾构固化土在标养条件下的28 d无侧限抗压强度可达5.38 MPa, 40℃条件下可达8.08 MPa,水稳系数达0.98。In order to achieve the resource utilization of high moisture content shield soil in underground engineering and explore the feasibility of using geopolymer materials to solidify shield soil,this paper adopts slag-base geopolymer to solidify shield soil.By studying the influences of alkali activator modulus,mineral ratio,alkali activator dosage and temperature on unconfined compressive strength and engineering performance of different types of shield-cured soil,the design of cured soil mix proportion was determined.The influence of geopolymer content on water stability of cured soil was studied.Microscopic analysis of shield-cured soil using SEM to reveal the solidification mechanism.The results show that under the proposed water solid ratio in the test,the two kinds of fluid shield-cured soil with different soil properties have good mechanical and engineering properties.The aggregate of slag base produces amorphous gel,which enhances the cementation and compactness between soil particles.The unconfined compressive strength of shield-cured soil with 22%dry soil mass as cementing agent can reach 5.38 MPa in 28 d under standard curing,8.08 MPa under 40℃curing,and the water stability coefficient can reach 0.98.

关 键 词：盾构固化土 地聚物 固化剂 最优配合比 工程性能 微观机理 

分 类 号：TU528[建筑科学—建筑技术科学]