混凝土早强剂低温性能试验研究  

Study on the Propery of Early-strength Agent of Concrete at Low Temperature

作　　者：张丰[1] 白银[1] 陈波[1] 宁逢伟[1] 吕乐乐 胡海明[1] ZHANG Feng;BAI Yin;CHEN Bo;NING Feng-wei;LYU Le-le;HU Hai-ming(Nanjing Hydraulic Research Institute,State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing 210029,China)

机构地区：[1]南京水利科学研究院、水文水资源与水利工程科学国家重点实验室,江苏南京210029

出　　处：《混凝土与水泥制品》2021年第7期1-6,共6页China Concrete and Cement Products

基　　金：国家重点研发计划项目(2018YFC0406702);国家自然科学基金项目(51739008);中央级公益性科研院所基本科研业务费专项(Y419004)。

摘　　要：从强度、凝结时间、水化热及混凝土工作性、耐久性等方面比较了5种混凝土早强剂在低温环境下的性能差异,综合评价了市售混凝土早强剂的低温使用效果。结果表明:5℃养护下,早强剂使砂浆7 d强度均有一定程度提高,但1 d强度仍比较低,且会使28 d强度倒缩;早强剂的掺入可促进低温下水泥的水化,使水化诱导期缩短,最大放热速率、放热量增大;掺D、E早强剂对混凝土工作性影响不大,满足实际工程施工性能的要求,可一定程度提高混凝土早期强度,但低温早强效果仍有限,且会导致混凝土后期性能下降。The performance differences of five kinds of commercial concrete early-strength agents at low temperature were compared from the perspectives of compressive strength,setting time,hydration heat,and workability and durability of concrete,and the application effect of the early-strength agents currently on the market was evaluated.The results show that under 5℃curing,the early-strength agent can increase the strength of the mortar to a certain extent,but the strength of 1 d is still relatively low,and it will shrink the strength of 28 d.The incorporation of the early-strength agent can promote the hydration of cement at low temperature,shorten the hydration induction period,and increase the maximum heat release rate and heat release.Adding D and E early-strength agents has little effect on the workability of concrete,which meets the requirements of actual engineering construction performance and can increase the early strength of concrete to a certain extent.However,the effect of low-temperature early-strength is still limited,and adding early-strength agents will cause the later performance of concrete to decline.

关 键 词：低温 早强剂 抗压强度 水化热 耐久性 

分 类 号：TU528[建筑科学—建筑技术科学]