在有不规则粒子形状的颗粒状材料中进行热摇
Yize Pan1, Xiaohui Gong1, Alessandro F Rotta Loria2
1Department of Civil and Environmental Engineering, Subsurface Opportunities and Innovations Laboratory, Northwestern University, Evanston, USA.
Scientific reports
|March 22, 2024
概括
周期性温度变化会导致沙子等颗粒状材料的不可逆转变形. 这种受粒子形状和应力影响的热摇减效应,会在多个循环中导致显著的紧缩.
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
- 热力学是一种热力学.
背景情况:
- 颗粒状材料在自然和人工环境中经历各种温度波动.
- 颗粒状材料对周期性温度变化的机械反应尚未得到充分理解.
- 粒子形状,应力,密度和温度振幅等关键因素尚未得到充分探索.
研究的目的:
- 研究周期性温度变化对颗粒材料,特别是沙子机械学的影响.
- 量化粒子形状,应力水平,相对密度和温度振幅对这种反应的影响.
主要方法:
- 在颗粒状材料上进行了先进的实验室实验,重点是沙子.
- 在受控条件下,对样品进行循环温度变化.
- 监测了变形和微观结构的变化.
主要成果:
- 周期性温度变化会导致沙子中的"热摇",导致不可逆转的大体变形.
- 这些变形是由于粒子热膨胀和收缩导致的微观结构重组造成的.
- 变形的程度取决于粒子形状,应力,密度和温度幅度.
结论:
- 热震动导致沙子和其他颗粒状材料在多个循环中发生显著的累积压缩.
- 这种现象可能对自然和人工系统的性能产生重大影响.
- 了解热振动对于预测热循环下的颗粒材料的长期行为至关重要.
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