来自建筑和拆除废物的热活化水泥用于路面基层稳定:巴西的一个案例研究
Valdir M Pereira1, Raphael Baldusco2, Patricia B Silva3
1National Institute on Advanced Eco-Efficient Cement-Based Technologies, Brazil. Escola Politecnica, University of São Paulo, São Paulo, Brazil.
概括
回收建筑和拆除废弃物 (CDW) 可用于制造有效的水泥和聚合物,用于路面底层. 这种创新方法减少了垃圾填埋垃圾,并促进了建筑材料的循环利用.
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
- 环境工程 环境工程
背景情况:
- 建筑和拆除废物 (CDW) 产量每年超过100亿,其中很大一部分被填埋.
- 迫切需要创新的回收方法来减轻环境影响并增强CDW的循环性.
研究的目的:
- 为了证明从CDW中开发回收水泥的可行性.
- 为路面底层应用优化CDW回收水泥与优质粉碎石 (WGCS).
- 通过试点规模的建设和现场测试来验证基于CDW的材料的性能.
主要方法:
- 利用各种CDW罚款来制造回收水泥.
- 用WGCS优化水泥含量,用于路面底层混合物.
- 从当地一家回收工厂扩大了CDW水泥和料的生产规模.
- 建造的试点路面部分和测量的场偏差.
主要成果:
- 在CDW水泥糊中,累积热量高达111J/g,压力强度约为16MPa.
- 使用CDW水泥和WGCS的路面底层实现了2-3MPa的不受限制的压力强度和3000MPa以上的弹性模量.
- 与波特兰水泥和常规颗粒基相比,使用CDW水泥的截面性能中等.
- 在CDW水泥段中,由于pozzolanic反应,随着时间的推移观察到偏移的减少.
结论:
- 回收的CDW罚款对于开发有效的水泥材料是可行的.
- 基于CDW的回收水泥和聚合物可以成功地用于路面底层.
- 在路面施工中使用CDW有助于减少废物和材料循环.
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