在冷解周期下的根性土壤的机械性能和扩展的二进制介质构成模型
Wei Luo1, Bo Xiang2, Enlong Liu3
1State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resources and Hydropower, Sichuan University, Chengdu, 610065, China.
Scientific reports
|August 21, 2023
概括
这项研究研究了季节性结土壤的机械特性,受融周期和根系的影响. 研究结果表明,结冰解周期会削弱土壤,而根则提高土壤的承载能力,从而改善了预测模型.
科学领域:
- 地质技术工程 地质技术工程
- 土壤力学 土壤力学
- 永久土科学 永久土科学
背景情况:
- 季节性结的土壤容易受到机械性质的改变,这是由于结解周期和根系的存在造成的.
- 了解这些变化对于寒冷地区的基础设施稳定至关重要.
- 现有的模型可能无法完全捕捉土壤,融和根之间的复杂相互作用.
研究的目的:
- 实验性地研究季节性结土壤在不同限制压力,结解周期和根含量下的机械特性.
- 开发和验证一个扩展的二进制介质模型,该模型包含结解周期对土壤行为的影响.
- 准确模拟土壤反应,包括应变软化和体积扩张.
主要方法:
- 对土壤样本进行了一系列排水三轴测试,其中包括各种限制压力 (25-200 kPa),冷解周期 (0-15) 和根体积比率 (0-3).
- 开发了一种扩展的二进制介质模型,将土壤抽象为结合和摩擦元素,并将根源抽象为非破坏性结合元素.
- 对于不同的土壤和根部件,利用了线性弹性和双硬化构成模型.
主要成果:
- 样本在低限压下表现出应变软化和体积膨胀,在高限压下体积收缩时表现出应变硬化.
- 增加的冷解周期导致承载能力下降和体积应变增加.
- 较高的根体积比率增加了承载能力,减少了体积应变.
结论:
- 开发的扩展二进制模型准确地预测了季节性结土壤的机械行为,包括应变软化和体积膨胀.
- 该模型有效地捕捉了结解周期的有害影响和根系的稳定影响.
- 这项研究为分析在季节性结环境下地质结构的稳定性和性能提供了有价值的工具.
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