石灰石粉对C60混凝土抗压性能及水化热的影响研究  

Study on Influence of limestone powder on compressive properties and hydration heat of C60 concrete

作　　者：黄先桃 申波[1,2] 吴洪梅 邓懋 陈松 谢青青 HUANG Xiantao;SHEN Bo;WU Hongmei;DENG Mao;CHEN Song;XIE Qingqing(Research Center of Space Structures,Guizhou University,Guiyang 550025,Guizhou,China;Key Laboratory of Structural Engineering of Guizhou Province,Guizhou University,Guiyang 550025,Guizhou,China)

机构地区：[1]贵州大学空间结构研究中心,贵州贵阳550025 [2]贵州大学贵州省结构工程重点实验室,贵州贵阳550025

出　　处：《建筑科学与工程学报》2024年第5期123-130,共8页Journal of Architecture and Civil Engineering

基　　金：国家自然科学基金项目(51468007);贵州省科技计划项目(黔科合基础[2018]1038)。

摘　　要：为探究石灰石粉对C60高强混凝土力学性能和水化热的影响,对不同石灰石粉比表面积和不同石粉含量的高强混凝土进行了抗压性能和水化放热试验。结果表明:石灰石粉的掺入能有效提高混凝土的抗压强度,其提升幅度介于1.3%~19.3%之间,在比表面积为6 000 cm^(2)·g^(-1)、石粉含量(质量分数)为5%~15%时混凝土抗压强度提升最明显;由于石粉的活性远低于水泥,随着石粉含量的增加,胶凝体系的总放热量逐渐降低且时间-水化放热速率曲线向左偏移,其中S15-6000组混凝土前期水化速率最快;在胶凝体系的水化产物中,掺入石粉后并未检测到新生成的物相,Ca(OH)_(2)峰值强度在石粉含量为15%时达到最高并伴随着生成大量C-S-H,这是由于石粉的掺入起到稀释效应,胶凝体系的水胶比增加使得水泥在水化时获得了充足的水量,此外,15%的石粉含量为胶凝体系提供了最佳钙含量,进一步促进了水化;大量C-S-H凝胶的生成为S15-6000组混凝土抗压强度提供了保证,且该组混凝土能较大程度发挥石粉作用。In order to study the influence of limestone powder content on the mechanical properties and hydration heat of C60 high-strength concrete,the experiment was carried out to analyze the mechanical properties and hydration heat release of high-strength concrete with different specific surface areas and contents of limestone powder.The results show that the addition of limestone powder can effectively improve the compressive strength of concrete,and the increase range is between 1.3%and 19.3%.The improvement of concrete compressive strength is the most obvious under the limestone powder specific surface area is 6000 cm^(2)·g^(-1) and the content is 5%-15%.Since the activity of stone powder is much lower than that of cement,with the increase of limestone powder content,the total heat release of cementitious system gradually decreases and the time-hydration heat release rate curve shifts to the left,among which the hydration rate of S15-6000 group concrete is the fastest in the early stage.No newly generated phase is detected in the hydration product of cementitious system with the addition of limestone powder.When limestone powder content is 15%,the peak strength of Ca(OH)_(2) reaches the highest and meanwhile generates a large amount of C-S-H gel.The reason is that the addition of limestone powder has a dilution effect,and the increase of the water-binder ratio of cementitious system makes the cement obtain sufficient water during hydration.In addition,15%limestone powder content provides the best calcium content for the cementitious system to further promote hydration.The formation of a large amount of C-S-H gel provides a guarantee for the development of compressive strength of S15-6000 group concrete,and the group can make full use of limestone powder to a greater extent.

关 键 词：石灰石粉 抗压强度 水化热 比表面积 胶凝体系 

分 类 号：TU528.31[建筑科学—建筑技术科学]