关于在活性化泡混凝土中应用回收混凝土废物粉末的实验研究
Dongsheng Zhang1,2, Weiwei Hao1, Qiuning Yang1
1School of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, China.
Materials (Basel, Switzerland)
|September 9, 2023
概括
在活性焦渣泡混凝土中的回收混凝土粉 (RCP) 提高了绝热性,减少了干燥收缩,但降低了机械性能和抗性. 即使使用50%的RCP,强度也符合标准.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 可持续的建筑材料 可持续的建筑材料
背景情况:
- 活性化水泥材料为传统的波特兰水泥提供了可持续的替代品.
- 回收混凝土粉 (RCP) 为建筑垃圾利用提供了一个机会.
- 调查RCP对活性渣 (AAS) 泡混凝土性能的影响对于其应用至关重要.
研究的目的:
- 评估不同循环混凝土粉末 (RCP) 替代率对基于活性 (AASR) 泡混凝土性能的影响.
- 为了确定平衡性能特征的最佳RCP内容.
- 评估AASR泡混凝土作为可持续建筑材料的可行性.
主要方法:
- 制备基于活性渣RCP (AASR) 的泡混凝土,其RCP质量分数为10%,20%,30%,40%和50%.
- 对AASR泡混凝土性能进行全面测试:流动性,吸水性,软化系数,压力强度,屈曲强度,干燥收缩,导热性和抗性.
- 与对照组 (0% RCP) 的比较分析.
主要成果:
- 随着RCP含量增加,流动性和软化系数下降;由于RCP的多孔结构,吸水率增加.
- 机械性能 (压力和屈曲强度) 随着RCP含量增加而下降,尽管28天的压力强度仍然高于0.6MPa标准.
- 添加RCP显著降低了导热率 (RCP50%的最低值为0.119W/m·K) 和干燥收缩率 (RCP30%的最低值是14.7%的减少),但降低了抗性.
结论:
- 在活性泡混凝土中用RCP部分替代渣,在隔热和干燥收缩控制方面具有好处.
- 增加的RCP含量会对机械强度和耐性产生负面影响,需要仔细设计混合物.
- AASR泡混凝土显示了可持续建筑的潜力,只要管理性能权衡,特别是对于在冷解周期下需要耐用性的应用.
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