混凝土用新型缓凝剂的制备及其性能评价  

Preparation and performance evaluation of new retarder for concrete

作　　者：马以宏 陈兴涛 汤雷[2] MA Yihong;CHEN Xingtao;TANG Lei(Zhongyifeng Construction Group Co.,Ltd.,Suzhou 218131 China;Nanjing Hydraulic Research Institute Materials and Structural Engineering Department,Nanjing 210029,China)

机构地区：[1]中亿丰建设集团股份有限公司,江苏苏州218131 [2]南京水利科学研究院材料结构研究所,江苏南京210029

出　　处：《混凝土》2024年第9期105-108,共4页Concrete

基　　金：国家自然科学基金重点项目“复杂地质环境下输调水工程灾害预警与快速抢险(第一课题)”(51739008)。

摘　　要：为了有效延长混凝土的凝结时间,提高混凝土的长距离泵送性能,以烯醇基聚氧乙烯醚TPEG、甲基丙烯酸MAA和丙烯酸磷酸酯单体FM-1为主要原料,通过自由基聚合的方式制备出了一种适合混凝土用的新型缓凝剂GRE-1,并对其综合性能进行了评价。试验结果表明:新型缓凝剂GRE-1的掺入能够有效改善水泥浆的流动性能,延长水泥浆的凝结时间,当其质量浓度为0.5%时,可大幅提高水泥浆的流动度,并能使水泥浆的初凝时间和终凝时间延长一倍以上;GRE-1还能与水泥浆中的阳离子产生结合作用,有效降低滤液中阳离子的浓度;GRE-1的掺入能够大幅提升水泥砂浆试件的早期抗压强度和抗折强度,改善其力学性能;GRE-1在混凝土中的应用效果明显优于常用市售缓凝剂HT-1和HP-1。研究结果认为研制的新型缓凝剂GRE-1可以有效改善混凝土的工作性能,能够满足混凝土长距离泵送的使用需求。In order to effectively extend the setting time of concrete and improve the long-distance pumping performance of concrete,a new type of retarder GRE-1 suitable for concrete was prepared by free radical polymerization with vinyl polyoxyethylene ether TPEG,methacrylic acid MAA and acrylic acid phosphate monomer FM-1 as the main raw materials,and its comprehensive performance was evaluated.The test results show that the new retarder GRE-1 can effectively improve the fluidity of cement slurry and prolong the setting time of cement slurry.When its mass concentration is 0.5%,the fluidity of cement slurry can be greatly improved,and the initial setting time and final setting time of cement slurry can be extended by more than one time;GRE-1 can also combine with cations in cement slurry to effectively reduce the concentration of cations in filtrate;The incorporation of GRE-1 can greatly improve the early compressive strength and flexural strength of cement mortar specimens,and improve their mechanical properties;The application effect of GRE-1 in concrete is obviously better than that of common commercial retarders HT-1 and HP-1.The research results show that the new retarder GRE-1 can effectively improve the working performance of concrete and meet the needs of concrete long-distance pumping.

关 键 词：混凝土 缓凝剂 流动度 凝结时间 力学性能 

分 类 号：TU528.042.3[建筑科学—建筑技术科学]