混掺再生粗骨料和再生微粉混凝土的早期力学性能  

Early Mechanical Properties of Concrete Mixed with Recycled Coarse Aggregate and Recycled Powder

作　　者：毕钰 秦拥军[1,2] 罗玲 姚子祺[1] 刘凤超 阳毅恒 BI Yu;QIN Yongjun;LUO Ling;YAO Ziqi;LIU Fengchao;YANG Yiheng(College of Civil Engineering and Architecture,Xinjiang University,Urumqi 830047,China;Xinjiang Civil Engineering Technology Research Centre,Urumqi 830047,China)

机构地区：[1]新疆大学建筑工程学院,乌鲁木齐830047 [2]新疆土木工程技术研究中心,乌鲁木齐830047

出　　处：《硅酸盐通报》2025年第2期623-633,共11页Bulletin of the Chinese Ceramic Society

基　　金：自治区重点研发项目(2022B03036);自治区自然科学基金重点项目(2022D01D27)。

摘　　要：针对建筑固废利用率较低的问题,本文对使用不同获取方式和取代方式的再生微粉与再生粗骨料制备的混凝土抗压强度进行了试验研究,并建立了同时掺入再生微粉和再生粗骨料混凝土的早期抗压强度时变规律预测模型,并分析了制备混凝土的碳足迹。研究包括超量取代与常量取代的对比,以及研磨获取的再生微粉与筛分获取的再生微粉的对比。结合扫描电子显微镜和压汞法对混凝土试样进行了微观测试,分析了混凝土强度变化微观层面的原因。结果表明,再生微粉对混凝土力学性能的影响比再生粗骨料明显。随着再生微粉掺量从0%增加到30%(质量分数),试块早期抗压强度的发展逐渐减慢,孔隙率则迅速增加,且多害孔的占比也会增加。此外,以再生微粉和再生粗骨料取代率为参数建立的再生混凝土早期抗压强度时变规律预测模型拟合程度良好,可在工程实践中作为参考。To address the issue of the low utilization rate of construction waste,this paper investigated the compressive strength of concrete prepared using recycled coarse aggregate and recycled powder from different acquisition methods and substitution methods.It also established a predictive model for the time-varying early compressive strength of concrete when mixing recycled powder and recycled coarse aggregate concrete,and analyzed the carbon footprint of the prepared concrete.The study included comparisons between over-substitution and standard substitution,as well as between recycled powder obtained by grinding and obtained by screening.Combined with scanning electron microscopy and mercury intrusion method,the micro-test of concrete samples was carried out,and the reasons for the micro-level change of concrete strength were analyzed.The results indicate that the impact of recycled powder on the mechanical properties of concrete is more significant than that of recycled coarse aggregate.As the content of recycled powder increases from 0%to 30%(mass fraction),the development of early compressive strength of the concrete gradually slows down.The porosity of concrete increases rapidly and the percentage of more hazardous hole also increases.In addition,the predictive model for the time-varying early compressive strength of recycled concrete established with the replacement rate of recycled powder and recycled coarse aggregate is well fitted,which can be used as a reference in engineering practice.

关 键 词：再生微粉 再生粗骨料 抗压强度 碳足迹 预测模型 微观分析 

分 类 号：TU528[建筑科学—建筑技术科学]