不同分子量SAP对活性粉末混凝土自收缩及早期水化进程的影响  

Influence of Different Molecular Weight Super Absorbent Polymer on Auto-Shrinkage and Early Hydration Process of Reactive Powder Concrete

作　　者：王中健 朱涵[1,2] 陈伟[1] Wang Zhongjian;Zhu Han;Chen Wei(School of Civil Engineering,Tianjin University,Tianjin 300350,China;Coastal Civil Engineering Structure and Safety Key Laboratory of the Ministry of Education,Tianjin University,Tianjin 300072,China;不详)

机构地区：[1]天津大学建筑工程学院,天津300350 [2]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072

出　　处：《石家庄铁道大学学报（自然科学版）》2019年第3期18-23,共6页Journal of Shijiazhuang Tiedao University(Natural Science Edition)

基　　金：国家自然科学基金(51078261)

摘　　要：将2种不同分子量的高吸水树脂(super absorbent polymer,SAP)作为内养护剂进行预吸水处理后引入到活性粉末混凝土(reactive powder concrete,RPC)中,研究其对RPC自收缩、早期水化进程及抗压强度的影响,并分析不同分子量SAP掺入的作用机理。自收缩试验表明,SAP的掺入对RPC有良好的减缩效果,额外引入水胶比为0.03时,掺入高、低分子量SAP的RPC在56 d龄期时的收缩率分别下降了46.6%和41.2%。等温量热试验表明,放热总量受SAP分子量高低的影响较大,低分子量SAP更有利于降低峰值放热速率与总放热量。抗压强度试验表明,低分子量SAP更有利于控制强度损失。故低分子量SAP在减缩、降低水化热、控制强度损失上较高分子SAP更具适宜性,因此更适合作为RPC内养护材料。Two kinds of super absorbent polymer(SAP)with different molecular weights were pretreated with water as internal curing agent incorporated into reactive powder concrete(RPC)to study their effects on auto-shrinkage,early hydration process,and strength.Auto-shrinkage test showed that SAP had better shrinkage reduction effect on RPC.When the additional water-cement ratio was 0.03,the auto-shrinkage of RPC with high molecular weight and low molecular weight SAPs decreased by 46.6%and 41.2%,respectively.The experimental results of hydration heat test showed that the cumulative hydration heat amount was greatly influenced by the molecular weight of SAP,and the low molecular weight SAP was more beneficial in reducing the peak hydration heat flow rate and the total hydration heat amount.Compressive strength tests showed that low molecular weight SAP was more conducive to controlling strength loss.Therefore,low molecular weight SAP was more suitable as internal curing material.

关 键 词：高吸水树脂 活性粉末混凝土 减缩 水化热 

分 类 号：TU502.4[建筑科学—建筑技术科学]