回收精细混凝土混凝土的环境影响和性能评估
Mudassar Munir Shah1, Usama Khalid2, Hassan Mujtaba3
1Department of Civil Engineering, Faculty of Infrastructure, Dalian University of Technology, Dalian, 116024, China.
概括
在混凝土中使用回收精细聚合物 (RFA) 为建筑垃圾提供了一个可持续的解决方案. 使用高达50%RFA的混凝土表现出可靠的性能,并显著减少对环境的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
- 土木工程 土木工程是指土木工程.
背景情况:
- 建筑和拆除废弃物 (CDW),特别是混凝土,给环境带来了挑战,特别是对发展中国家来说.
- 使用回收精细聚合物 (RFA) 而不是新鲜的精细聚合物 (FFA) 是一种可持续的方法来管理混凝土废物.
- 这项研究解决了对环保建筑材料和减少废物战略的需求.
研究的目的:
- 评估混凝土的性能,其中包含不同百分比的RFA.
- 评估RFA对混凝土机械性能和耐久性的影响.
- 量化使用RFA在混凝土生产中的环境效益.
主要方法:
- 实验室测试混凝土混合物,其RFA替换率为0%至100%.
- 研究压力强度,抗拉强度,弹性模量和可加工性.
- 评估离子透率,化学耐药性和聚合物质量.
- 生命周期评估,以确定环境影响,如全球变暖潜力,水生环保和酸化.
主要成果:
- 100%的RFA替代导致压力强度估计减少30%,拉伸强度减少35%,弹性模量减少20%,可加工性减少79%.
- 在测试条件和混合设计下,高达50%RFA的混凝土表现出可靠的性能.
- 与100%的FFA混凝土相比,使用50%RFA混凝土显著减少了环境影响:47%的全球变暖潜力,40%的水生肥胖,18%的水生酸化.
结论:
- 回收精细聚合物 (RFA) 可以有效地用于混凝土生产,为新鲜精细聚合物 (FFA) 提供可行的替代品.
- 最佳性能和显著的环境效益可以通过在混凝土中更换高达50%的RFA来实现.
- 这种方法通过减少浪费和减轻环境退化,为可持续建筑实践做出了贡献.
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