米灰对超高强度工程混凝土复合材料 (UHS-ECC) 的机械性能的影响
Feifei Liu1, Baohong Jin2, Qi He1
1Architectural Engineering Institute, Zhejiang Tongji Vocational College of Science and Technology, Hangzhou, China.
PloS one
|April 18, 2024
概括
米灰 (RHA) 可以代替水泥在超高强度工程水泥复合材料 (UHS-ECC) 中,以减少二氧化碳排放. 20%的最佳RHA含量产生了高强度和柔性,提高了可持续性.
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.
- 可持续建筑 可持续建筑
背景情况:
- 水泥生产对全球二氧化碳排放做出了重大贡献 (8%).
- 超高强度工程混凝土复合材料 (UHS-ECC) 通常需要大量的水泥含量,这给可持续性带来了挑战.
- 米灰 (RHA) 是一种具有作为补充水泥材料的潜力的pozzolanic副产品.
研究的目的:
- 调查使用RHA来替代UHS-ECC中的水泥的可行性.
- 评估RHA整合对UHS-ECC机械性能和微观结构的影响.
- 为了确定可持续和高性能UHS-ECC的最佳RHA剂量.
主要方法:
- 在UHS-ECC混合物中系统地用不同百分比的RHA替换水泥.
- 试验测试砂的流动性,压力强度和拉伸性能 (强度,应变,能量).
- 微结构分析以了解RHA对纤维桥接和伪应变硬化能量 (PSHenergy) 的影响.
主要成果:
- 加入RHA降低了砂的流动性.
- 最高的压力强度 (130.3 MPa在28天) 达到20%的RHA.
- 拉力强度最初增加,然后随着RHA含量而下降,而拉力应变和应变能量显示出相反的趋势.
- 低于20%的RHA含量降低了纤维桥梁能量和PSHenergy,与柔性降低相关.
结论:
- 在UHS-ECC中,RHA可以有效地用作补充的水泥材料,以减少对环境的影响.
- 建议RHA剂量不超过20%,以保持超高强度,可接受的可加工性和高拉伸柔性之间的平衡.
- 该研究强调了RHA在开发可持续和高效的UHS-ECC方面的潜力.
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