新的实验证据表明,用氧化干燥激活砂的收缩
Marco Sirotti1, Brice Delsaute1, Stéphanie Staquet1
1BATir Department, Université Libre de Bruxelles, CP194/02, 50 Avenue F.D. Roosevelt, 1050 Brussels, Belgium.
Materials (Basel, Switzerland)
|August 26, 2023
概括
活性渣 (AAS) 显示出作为可持续水泥替代品的希望,但高干燥收缩影响耐用性. 这项研究确定了影响AAS收缩的溶液与粘合剂比率和微裂纹等因素.
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:
- 活性渣 (AAS) 由于其有利的机械和化学性能,为普通波特兰水泥 (OPC) 提供了一个可持续的替代品.
- 在AAS中,高干燥收缩率对其在建筑应用中的长期耐用性构成重大挑战.
研究的目的:
- 为了研究六种活性渣/氧化砂组合物的干燥收缩行为.
- 确定影响干燥收缩的关键现象,包括度,溶液与粘合物比率,自身收缩,爬行合规性,微裂变和碳化.
主要方法:
- 对六种AAS/氧化砂组合物的实验分析.
- 对因素的评估:度,溶液与粘合剂比 (s/b),自生收缩,爬行合规性,微裂变和碳化.
- 长期监测材料特性,长达112天.
主要成果:
- 干燥收缩大小与激活溶液的度没有相关性.
- 发现增加溶液与粘合剂比率 (s/b) 会增加干燥收缩.
- 自生变形长期保持显著;爬行顺应受干燥的影响,但不是收缩大小.
- 干燥引起的微裂显著影响了干燥收缩.
- 碳化取决于激活溶液的度,其物质效应尚不清楚.
结论:
- 溶液与粘合剂的比率和干燥引起的微裂纹是影响AAS干燥收缩的关键因素.
- 虽然自身变形是显著的,但爬行合规性并不直接驱动收缩大小.
- 需要进一步的研究来澄清碳化对AAS耐久性的影响.
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