被高温处理的破碎的gabbro的动态行为
Xianhuan Liu1, Hailiang Jia1, Chao Wang1
1College of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an, Shaanxi, 710000, China.
Heliyon
|October 21, 2024
概括
高温改变了gabbro的表面和质量,导致微裂和碎片化. 强度和刚度在500°C左右达到顶峰,在800°C时由于广泛的损坏而急剧下降.
科学领域:
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
- 材料科学 材料科学 材料科学
背景情况:
- 深度工程项目面临高地热效应,这使得爆炸挖掘具有挑战性.
- 了解在热应力下破碎岩石的行为对于安全性和效率至关重要.
研究的目的:
- 为了研究高温对破碎石的动态裂变特征的影响.
- 分析微观结构的变化及其与机械性质的相关性.
主要方法:
- 使用Split Hopkinson压力棒 (SHPB) 装置进行动态分裂试验.
- 通过扫描电子显微镜 (SEM) 进行微结构分析.
- 在高温下评估表面色度和质量变化.
主要成果:
- 高温显著改变了gabbro的表面色度和质量.
- 微观结构从最小的微裂演变为500°C以上的广泛碎片化.
- 分裂强度,峰值应变和动态弹性模量显示在500°C左右的临界点,在800°C显著下降.
结论:
- 温度极大地影响了gabbro的机械性能,其最佳强度在500°C左右.
- 裂角度在故障机制中起着重要作用,特别是在600°C以下.
- 断裂主要由拉力和剪切机制主导,受裂几何形状和温度诱导损伤的影响.
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