基于资源的水泥固体废物混凝土的机械和收缩特性研究
Shikai Ning1,2, Xidong Jiang1,2, Bin Li1,2
1China Railway Construction Bridge Engineering Bureau Group Northwest Engineering Co., Ltd., Yinchuan 750021, China.
Materials (Basel, Switzerland)
|January 11, 2024
概括
回收的建筑垃圾,包括-渣和钢渣,为铁路配件制造环保混凝土. 这种新的混凝土表现出优越的机械强度和减少的收缩,提高了耐用性和可持续性.
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.
- 环境科学 环境科学
背景情况:
- 固体废物回收为节能和环境管理提供了显著的好处.
- 开发可持续建筑材料对于减少填埋场负担和促进循环经济至关重要.
研究的目的:
- 开发和评估一种新的环境保护混凝土,利用多来源的固体废物用于铁路配件设施.
- 调查钢含量,水泥剂量和年龄对混凝土机械性能和收缩行为的影响.
主要方法:
- 准备七种混凝土混合物,其中不同比例的 - 渣,钢渣,飞灰和回收麦卡达姆.
- 性能测试包括不受限制的压力强度,分裂强度,干燥收缩和温度收缩.
- 对特定混合物 (3SR-60) 的水化过程进行分析,以了解微观结构的发展.
主要成果:
- 指定为3SR-60的混凝土混合物表现出优越的机械强度,与其他具有类似水泥剂量的混凝土混合物相比.
- 温度收缩应变受废弃物残留比例,水泥剂量和温度波动的影响,观察到的最低系数在0-10°C之间.
- 干燥收缩率随着废物残留量增加而减少,但随着水泥含量增加而增加,在30天后稳定下来.
结论:
- 开发的混凝土,特别是SR-60,具有良好的机械性能和收缩性能.
- 微观结构分析显示,酸水合物 (C-S-H) 和酸 (AFt) 的持续发展,导致结构更密集,对外部干扰有更强的抵抗力.
- 该研究证实了在铁路应用中使用回收的多来源固体废物在混凝土中的可行性,有助于可持续的建筑实践.
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