早期固化实验对ECO-UHPC机械性能和微观结构的影响,由黄金尾带砂制成的ECO-UHPC
Qi Ouyang1, Xianxiang Zhou1, Xian Liang1
1College of Civil Engineering and Architecture, Quzhou University, Quzhou 324000, China.
Materials (Basel, Switzerland)
|February 26, 2025
概括
精细的黄金尾矿砂 (GTS) 可以取代石英砂在经济的超高性能混凝土 (ECO-UHPC). 热固化显著提高了ECO-UHPC强度,并在使用GTS时减少了重金属漏.
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:
- 金矿开采产生了大量的细金尾矿 (GTS).
- 石英砂是超高性能混凝土 (UHPC) 的一个昂贵的组成部分.
- 利用废弃物GTS为混凝土生产提供了一个可持续和经济的替代方案.
研究的目的:
- 调查在经济性超高性能混凝土 (ECO-UHPC) 中用GTS取代石英砂的可行性.
- 评估ECO-UHPC的机械性质和浸出毒性,使用不同的GTS替代率和早期固化条件.
- 使用SEM和MIP了解ECO-UHPC的微结构行为.
主要方法:
- 准备ECO-UHPC使用0%,25%,50%,75%和100%的GTS替代石英砂.
- 在四种固化条件下 (WC,HWC,HAC,CC) 对立方压力强度,弹性模量和镜压力强度的实验分析.
- 使用SEM和MIP评估漏毒性和微观结构分析.
主要成果:
- 整合GTS稍微降低了新鲜的ECO-UHPC流动性,但显著提高了热固化强度 (高达CC的+57.7%).
- 热固化ECO-UHPC强度与石英混凝土相当或高于石英混凝土,特别是在50%的GTS替代下.
- 热固化,特别是联合固化 (CC),有效地限制了重金属的出.
结论:
- 废GTS是可行的部分或完全替代ECO-UHPC中的石英砂,保持机械性能和环境安全.
- 早期的热固化方案对于提高基于GTS的ECO-UHPC的强度和减轻泄漏风险至关重要.
- 这项研究为使用回收材料的可持续建筑实践提供了宝贵的见解.
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