泵送碱式硫酸镁水泥混凝土的制备和性能  

Preparation and performance of pumped basic magnesium sulfate cement concrete

作　　者：曾翔超 余红发[2,3] 麻海燕[3] 张娜[3] ZENG Xiangchao;YU Hongfa;MA Haiyan;ZHANG Na(Department of Civil Engineering,Yangtze Normal University,Chongqing 408100,China;College of Civil Engineering and Water Resources,Qinghai University,Xi′ning 810016,China;Department of Airport and Civil Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)

机构地区：[1]长江师范学院土木学院,重庆408100 [2]青海大学土木工程学院,青海西宁810016 [3]南京航空航天大学机场与土木工程系,江苏南京210016

出　　处：《哈尔滨工程大学学报》2024年第2期270-276,共7页Journal of Harbin Engineering University

基　　金：重庆市自然科学基金项目(CSTB2022NSCQ-MSX0426);国家自然科学基金项目(51678304);重庆教育委员会科学技术研究计划重点项目(KJZD-K202201406)。

摘　　要：碱式硫酸镁水泥混凝土是新开发出来不久的混凝土材料,具有高抗拉强度、抗冲击和耐腐蚀等优点,但由于其较小的塌落度,限制了其工程应用。本文试验研究了不同掺量萘系减水剂对泵送碱式硫酸镁水泥混凝土塌落度和强度的影响,确定强度等级C30、C40、C50和C60的萘系高效减水剂适宜掺量分别为2.0%、1.2%、1.5%和1.8%。分别研究了掺粉煤灰型和矿渣型泵送碱式硫酸镁水泥混凝土基本力学性能及在海水浸泡、淡水浸泡1280 d后的强度保留率并进行机理分析,发现粉煤灰型泵送碱式硫酸镁水泥混凝土抗海水腐蚀性较好,适合东部沿海地区应用;随着海水暴露时间的延长,泵送碱式硫酸镁水泥混凝土的Df值呈现幂函数的降低关系。本文还对大气中暴露2400 d的钢筋泵送碱式硫酸镁水泥混凝土小梁进行观测,未有锈涨现象。本文为碱式硫酸镁水泥混凝土在工程领域的应用具有重大意义。Basic magnesium sulfate cement concrete(BMSC)is a newly developed type of cement concrete material with high tensile strength,impact resistance,and corrosion resistance.However,a low slump limits its application in civil engineering.The effect of naphthalene superplasticizer with different contents on the slump and strength of pumped BMSC was studied,ascertaining suitable contents of naphthalene superplasticizer for a pumped BMSC(PBMSC)with a strength grade of C30,C40,C50,and C60 as follows:2.0%,1.2%,1.5%,and 1.8%,respec-tively.The basic mechanical properties of pumped BMSC mixed with fly ash and slags,as well as the strength reten-tion rate after seawater immersion and fresh water immersion for 1280 d,were studied,and the mechanism was ana-lyzed.PBMSC with fly ash has good corrosion resistance to seawater,suitable for the eastern coastal regions of China.With increasing exposure time in seawater,the Df value of PBMSC shows the decreasing behavior of a power func-tion.The reinforced PBMSC beams exposed to the atmosphere for 2400 d were also observed and showed no rust phe-nomenon.This paper is of great importance for the application of BMSC in the civil engineering industry.

关 键 词：泵送碱式硫酸镁水泥混凝土 萘系高效减水剂 强度保留率 力学性能 耐久性能 掺量 塌落度 水化 

分 类 号：TU375[建筑科学—结构工程]