孔隙性和水泥控制了人工水泥尾矿在液压负荷下对高压的反应
Nilo Cesar Consoli1, João Vítor de Azambuja Carvalho2, Alexia Cindy Wagner1
1Graduate Program in Civil Engineering, Universidade Federal do Rio Grande do Sul, Porto Alegre, 90035-190, RS, Brazil.
Scientific reports
|November 26, 2024
概括
这项研究引入了一种新的孔隙性/水泥指数,用于预测水泥化铁矿石尾矿 (IOT) 的行为. 该索引有助于设计IOT堆和控制采矿应用的压缩.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 采矿工程 采矿工程 采矿工程
背景情况:
- 混凝土尾矿对于采矿操作至关重要,如填充和堆叠.
- 了解水泥化铁矿石尾矿 (IOT) 的压缩行为对于安全高效的设计至关重要.
研究的目的:
- 为了研究各种条件下的IOT与波特兰水泥混合的压缩行为.
- 引入和验证一个新的孔径/水泥指数,用于预测水泥IOT混合物的性能.
- 分析凝固和压缩对尾矿同otropisation和产量后压缩行为的影响.
主要方法:
- 同位体压缩试验是同位体压缩试验.
- 脉冲速度测试可以测试脉冲速度.
- 不受限制的压缩试验.
- 孔隙性/水泥指数 (η/Civ) 的分析
主要成果:
- 孔隙性/水泥指数 (η/Civ) 有效地预测了压缩过IOT-波特兰水泥混合物的弹性和塑性特征.
- 添加水泥和压缩促进了尾矿的异型化.
- 不化样本的明显的初始孔隙性汇聚到一个独特的产后压缩线 (PYCL) 超过100MPa,而化样本甚至在120MPa时也没有达到独特的PYCL.
结论:
- 孔径/水泥指数为在水泥IOT堆设计中选择水泥含量和目标密度提供了一种新的方法.
- 严格的现场压缩控制对于管理尾矿性质至关重要.
- 该研究提供了一种对人工凝固尾矿剂量和技术控制的方法.
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