摘要
低热微膨胀水泥(LHEC)具有低水化热和微膨胀等特性,也是一种低碳型水泥。分别以低热微膨胀水泥和矿渣硅酸盐水泥(PS)制备高强砂浆,设置20、45、70℃三种水养护条件,比较研究了2种水泥砂浆在不同水养护温度下的强度和膨胀率,并结合XRD和SEM分析,对相关机制进行了探讨。结果表明:LHEC高强砂浆与PS高强砂浆相比,具有更高的抗折强度、折压比和膨胀率;前者抗折、抗压强度和膨胀率在45℃时最高,而后者抗折、抗压强度在70℃时最高,膨胀率随温度变化不明显。其原因为LHEC高强砂浆中引入了较多的钙矾石相(AFt),水养护温度促进了矿渣的水化及AFt形成,但过高的水养护温度会使AFt向单硫型水化硫铝酸钙相(AFm)转变。
Low heat expansion cement(LHEC)is a type of low-carbon cement with low heat of hydration and micro expansion properties.The high-strength mortars were prepared with LHEC and Portland-slag cement(PS),and three water curing conditions were set at 20,45,70℃.The strength and expansion of the mortars at different curing temperatures were compared.Based on XRD and SEM analysis,the related mechanism was discussed.The results show that the high-strength mortars prepared by LHEC have higher flexural strength,flexural-to-compressive ratio and expansion than that prepared by PS.The flexural strength,compressive strength and expansion are highest at 45℃for the former,and highest at 70℃for the latter.The expansion of the latter is very small and doesn't changed obviously with temperature.High-strength mortars prepared by LHEC introduces more ettringite(AFt),and the curing temperature promotes the hydration of slag and the formation of AFt,however causes the transformation of AFt to the calcium sulphoaluminate hydrates(AFm)when it is too high.
作者
詹早良
金冰欣
章迪
武双磊
徐迅
ZHAN Zaoliang;JIN Bingxin;ZHANG Di;WU Shuanglei;XU Xun(Zhejiang Dingfeng Technology Co.Ltd.,Shaoxing 312000,China;School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China;School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang 621010,China)
出处
《新型建筑材料》
2024年第3期24-28,共5页
New Building Materials
基金
四川省科技计划项目(2023YFSY0019)。
关键词
普通硅酸盐水泥
低热微膨胀水泥
高强砂浆
强度
膨胀率
Portland cement
low heat expansion cement
high-strength mortar
strength
expansion rate
