活化掺合料对低温混凝土性能的影响  

Influence of activated admixtures on properties of cryogenic concrete

作　　者：李志远 李立辉 张斌 LI Zhiyuan;LI Lihui;ZHANG Bin(Research Institute of Highway, Ministry of Transport,Beijing 100888,China)

机构地区：[1]交通运输部公路科学研究所,北京100888

出　　处：《水利科学与寒区工程》2021年第2期53-56,共4页Hydro Science And Cold Zone Engineering

摘　　要：为了探究活化掺合料对低温混凝土的影响,选用降低钙矾石成核类型的活化材料ONE@-10和提供铝酸钙的活化材料CAH@-10掺入混凝土中,通过实验测试不同活性材料掺入下混凝土的塑性黏度、低温水化温度和抗压强度,分析了两种活性掺合料对低温混凝土工作性能、水化放热量和强度形成的影响。研究表明:掺活化材料ONE@-10混凝土具有较好的流动性和工作性,恒低温下持续自放热量大,由负温转正温后28 d强度与正温养护试件相当。掺活化材料CAH@-10混凝土流动性和工作性下降显著,在负温下具有比活化材料ONE@-10更强的强度发展和更小的水化放热量,但是其水化产物不稳定,后期强度发生倒缩现象,不利于重要结构部位使用。The activated materials that reduced the nucleation type of ettringite(ONE@-10)and that provided calcium aluminate(CAH@-10)were selected and mixed into concrete to explore the influence of activated admixtures on cryogenic concrete.The plastic viscosity,cryogenic hydration temperature and compressive strength of concrete were tested to analyze the influences of two kinds of activated admixtures on the concrete properties,hydration heat release and strength formation of cryogenic concrete.The results show that concrete mixed with activated material(ONE@-10)has good fluidity and workability,and the continuous self-releasing heat is large at constant low temperature The strength at 28 days after changing from negative temperature to positive temperature is equivalent to that of the positive temperature curing specimen.The fluidity and workability of concrete mixed with activated material(CAH@-10)decrease significantly.Under negative temperature,concrete of activated material(CAH@-10)has stronger strength development and less hydration heat release than that of activated material(ONE@-10),but the hydration products are unstable and its strength will shrink later,which is not beneficial to the use of important structural parts.

关 键 词：低温混凝土 活性材料 塑性黏度 水化放热 负温养护 

分 类 号：TU528.041[建筑科学—建筑技术科学]