高活性复合掺和料早期水化特性及其力学性能  

Study on Early Hydration Characteristics and Mechanical Properties of High Active Mineral Admixture

作　　者：蓝堂伟 李玉香[1] 郑爱国 蒋奥 LAN Tangwei;LI Yuxiang;ZHEN Aiguo;JIANG Ao(School of Materials Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Chengtie Deyang Railway Co.Ltd,Deyang 618007,Sichuan,China)

机构地区：[1]西南科技大学材料科学与工程学院,四川绵阳621010 [2]成铁德阳轨道有限公司,四川德阳618007

出　　处：《西南科技大学学报》2019年第3期48-53,共6页Journal of Southwest University of Science and Technology

基　　金：四川省教育厅科研项目(17ZA0395)

摘　　要：引入掺和料是提高无砟轨枕混凝土的脱模强度、后期力学性能及耐久性的重要措施之一。借助单纯重心设计法,采用矿渣粉、粉煤灰与高活性粉体A制备高活性复合掺和料,研究复合掺和料组成对早期活性指数、水化热以及混凝土抗压强度的影响。结果表明:复合掺合料的组成对其活性指数影响较大,并体现出明显的复合增强效应;高活性粉体A与矿渣粉二元复掺的混凝土1 d与28 d活性指数均达118%;3 d龄期后矿渣粉放热增加,而粉煤灰水化放热一直较低,矿渣粉或粉煤灰与高活性粉体A二元复掺时浆体1 d水化放热差别很小;三元复掺混凝土的复合增强效应优于二元复掺,三元复掺混凝土28 d与60 d抗压强度分别达68.6 MPa和79.6 MPa。Introduction of admixture is one of the important measures to improve the demoulding strength,later mechanical properties and durability of ballastless sleeper concrete.In the paper,by means of simplex centroid design method,high active admixture was prepared by using slag powder,fly ash and high activity powder A.The influences of compositions of composite admixtures on early activity index,hydration characteristics and concrete compressive strength were studied.The results show that composition of composite admixtures has a great influence on the early activity indexes,and shows obvious composite strengthening effect.Activity indexes of 1 d and 28 d of the binary admixture of highly active powder A and slag powder reach 118%.After 3 d,the hydration heat of slag powder increases.The hydration heat of fly ash is low within 7 days.There is little difference with the 1 d hydration heat of cement slurry when slag powder or fly ash is mixed with highly active powder A.The composite strengthening effect of ternary concrete is better than that of binary concrete.Compressive strength of ternary concrete is 68.6 MPa at 28 days and 79.6 MPa at 60 days.

关 键 词：复合掺和料 单纯重心设计 活性指数 混凝土 水化热 抗压强度 

分 类 号：TU528[建筑科学—建筑技术科学]