在暴露于高温后,尾矿混凝土的机械性能
Man Xu1, Hanzhao Zhang1, Jian Yuan2
1School of Civil Engineering and Transportation, Northeast Forestry University, Harbin, 150090, China.
Heliyon
|December 11, 2023
概括
高温显著降低了混凝土的性能,质量损失和应变增加,而峰值应力和弹性模量减少. 添加25%的尾矿可以减轻这种高温损伤.
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.
- 混凝土技术 混凝土技术
背景情况:
- 混凝土的机械性能对于结构完整性至关重要.
- 高温,如火灾,可以严重损害混凝土的性能.
- 尾矿呈现出一种潜在的补充性水泥材料.
研究的目的:
- 为了研究高温和尾矿替换率对混凝土机械性能的影响.
- 为了确定最佳的尾矿含量,以抗高温.
- 在合的热和替换条件下开发具体行为的预测模型.
主要方法:
- 在不同温度 (20-800°C) 下测试了75个混凝土镜,并测试了尾矿的替换比率 (0-100%).
- 分析轴向压缩故障模式和关键机械性能 (峰值应力,峰值张力,弹性模量,质量损失).
- 适应基于实验数据的预测公式,用于合条件.
主要成果:
- 温度升高加剧了混凝土的故障;质量损失和峰值应变增加,而峰值应力和弹性模量下降,在800°C显著降解.
- 质量损失与尾矿含量线性增加.
- 峰值应力,峰值张力和弹性模量最初增加,然后随着更换比率而减少,其中25%显示出更好的高温性能.
结论:
- 温度是在轴向压缩下降解混凝土的主要因素.
- 25%的尾矿更换比率提高了混凝土对高温损坏的抵抗力.
- 开发的公式准确地预测了在温度和替换比率效应的结合下混凝土的性能.
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