通过冲击和静态压缩方法制备的具有不同颗粒大小的岩石类材料的机械性能和裂纹演变
Qi Hu1,2, Qinglin Li1,2, Xingyan Liu1,2
1College of Water Conservancy & Architectural Engineering, Shihezi University, Shihezi 832003, China.
Materials (Basel, Switzerland)
|May 7, 2025
概括
静态压缩增强了细岩沙的机械性能,而冲击压缩则有利于更粗的沙和石英沙. 压缩方法显著影响岩石类材料的裂演变和故障模式.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 是一种材料科学.
- 岩石机械学 岩石机械学
背景情况:
- 了解颗粒材料的机械行为对于地质技术应用至关重要.
- 压缩方法显著影响土壤和岩石类材料的微观结构和宏观性质.
- 颗粒的大小和类型在材料对压缩和机械负荷的反应中起着至关重要的作用.
研究的目的:
- 研究静态与冲击压缩对岩石类材料机械性能和裂演变的影响.
- 分析不同颗粒大小 (岩石和石英砂) 如何影响这些效应.
- 为了比较压缩样本的微观结构与天然岩石类似物.
主要方法:
- 单轴压缩试验是在细 (0.075-0.18毫米) 和粗 (0.22-0.5毫米) 岩石沙和粗 (0.22-0.5毫米) 石英沙的样本上进行的.
- 采用数字图像相关性 (DIC) 技术来监测表面变形和裂传播.
- 用静态和冲击压缩方法准备样本,以达到1.82 g/cm3的密度或相当的压缩能量 (254.8 J).
主要成果:
- 静态压缩在细岩沙中产生了更高的弹性模量和峰值强度,而在相同密度的粗岩和石英沙中,冲击压缩优越.
- 在相当的压缩能量下,机械性能排名为:石英沙>粗岩沙>细岩沙.
- 静态压缩导致拉力分裂故障,而冲击压缩导致剪切主导的故障模式与碎形应变模式.
结论:
- 压缩方法的选择极大地影响颗粒材料的机械性能和故障机制,颗粒大小是关键因素.
- 静态压缩促进了拉力裂纹的传播,而冲击压缩则诱导了剪切带和碎形结构.
- 微观结构分析显示,压缩样本与天然沉积岩之间存在明显的相似之处,这取决于压缩方法和颗粒特征.
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