在不同的相对密度和水分含量下,珊瑚砂的应变速率的影响
Kai Dong1, Kun Jiang1, Wenjun Ruan1
1School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Materials (Basel, Switzerland)
|June 28, 2023
概括
这项研究表明,珊瑚砂中较高的相对密度降低了应变率对刚性的敏感性. 含水量会影响珊瑚砂中的水分.
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
- 土壤力学 土壤力学
背景情况:
- 珊瑚砂是沿海和离岸工程中的关键材料.
- 了解其在冲击负荷下动态机械性能对于结构设计和安全至关重要.
- 现有的研究往往忽视了相对密度和水分含量对动态行为的综合影响.
研究的目的:
- 研究相对密度和水分含量对珊瑚沙的动态性质的影响.
- 分析应力-应变行为和在高应变率下产量特征.
- 建立这些因素与动态机械反应之间的相关性.
主要方法:
- 使用37毫米直径的分裂霍普金森压力杆 (SHPB) 装置进行冲击负荷测试.
- 在不同相对密度和水分含量的珊瑚沙样本上进行了测试.
- 在460s-1到900s-1的应变速率下,在单轴应变压缩下获得的应力-应变曲线.
主要成果:
- 相对密度的增加使得珊瑚沙的刚性对应变率不那么敏感,这归因于可变的断裂能量效率.
- 含水量诱导了最初的硬化,软化与延展率相关;水滑导致更高的速度更显著的软化.
- 收益率特征揭示了对体积压缩反应的洞察力,表明需要指数构成模型.
结论:
- 相对密度和水分含量显著影响珊瑚沙的动态机械性能.
- 应变速率的影响由密度和水的存在来调节,滑效应在更高的速率下表现出来.
- 这些发现需要对构成模型进行调整,以准确地表示珊瑚沙的动态行为.
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