在路面混凝土应用中使用回收砂作为细型聚合物
Ali Mardani1, Daniel Hatungimana2, Şemsi Yazici3
1Department of Civil Engineering, Eng. Faculty, Bursa Uludag University, Nilüfer, Bursa, Turkey.
Heliyon
|January 25, 2024
概括
回收砂聚合物 (RMA) 可以用于路面混凝土,但其耐久性影响取决于混凝土的强度. 使用60%RMA的低强度混凝土显示出最小的性能损失,与高强度混凝土不同.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 可持续建筑 可持续建筑
背景情况:
- 在混凝土生产中,建筑和拆除废弃物 (CDW) 的回收正在增加.
- 粗回收聚合物被广泛使用,但精细分数,如回收砂聚合物 (RMA),由于异质性和不良性能而带来挑战.
- RMA 提出了一个潜在的解决方案,用于在具体应用中使用精细的 CDW.
研究的目的:
- 评估在路面混凝土中使用回收砂聚合物 (RMA) 的可行性.
- 评估RMA对混凝土耐用性的影响,特别是耐候性和耐磨性.
- 为了确定混凝土强度等级和水与粘合剂比率对RMA性能的影响.
主要方法:
- 研究了三种混凝土强度等级,其水与粘合剂 (w/b) 比率为0.4,0.5和0.6.
- 用RMA以0%,20%,40%和60%的体积率取代天然沙子.
- 通过水吸附性,耐磨性和结/解 (F/T) 循环测试来评估耐用性.
主要成果:
- 使用RMA的高强度混凝土 (w/b=0.4) 显示出显著的耐久性降低 (高达25%的吸附性,18%的磨损性,22%的F/T).
- 采用60%RMA的低强度混凝土 (w/b=0.6) 在强度和耐久性方面仅呈现了边际的下降 (13%的吸附性,8%的磨损,12%的F/T).
- RMA对耐久性的不利影响取决于混凝土的强度类别.
结论:
- 在路面混凝土中使用RMA取代自然砂的最大取代率必须根据混凝土强度等级进行调整,以确保可接受的耐用性.
- 较低强度的混凝土混合物更能耐受较高的RMA百分比,而不会影响基本性能特征.
- 在路面混凝土中,RMA可以有效地使用,特别是在较低强度的混凝土中,这有助于可持续的建筑实践.
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