在动态负载下对季节性地下土壤的变形特征进行实验研究
Dongwei Li1, Zecheng Wang2, Zhiwen Jia2
1College of Civil Engineering and Architecture, Dalian University, Dalian, China.
PloS one
|August 26, 2024
概括
中国西北部的地下土壤在融周期和周期性负荷下减弱. 了解水含量和压力等因素对于弹性高速公路建设至关重要.
科学领域:
- 地质技术工程 地质技术工程
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
背景情况:
- 中国西北地区的高速公路基础设施面临着土壤下层土壤的挑战,土壤在循环负荷和冷解周期下易受性能变化的影响.
- 了解地下土壤的行为对于在季节性结地区有效设计和建设高速公路至关重要.
研究的目的:
- 调查结冰解周期,含水量,限制压力和加载率对地下土壤变形和循环加载下的机械性能的影响.
- 为优化高速公路设计和缓解季节性结环境中的地下层问题提供数据.
主要方法:
- 对地下土壤变形特征和机械性能进行实验分析.
- 在循环负荷测试中,冷解周期,含水量,限制压力和负载率的系统变化.
主要成果:
- 动态加载使地下土壤变软,累积应变随着结解周期和含水量而增加,但随着限制压力 (最终应变<1%) 而下降.
- 失效压力随着结解周期 (224.52 kPa 到 196.76 kPa) 呈指数级下降,随着含水量增加 (377.1 kPa 到 151.5 kPa) 呈线性下降.
- 故障应力随着限制压力 (151.6 kPa 到 274.5 kPa) 和负载率 (200.46 kPa 到 210.62 kPa) 线性增加.
结论:
- 结冰解周期和水含量显著降低了下层土壤的强度,而限制压力和加载率提高了它.
- 该研究为在季节性结地区设计可持续高速公路提供了关键数据.
- 调查结果为防止和减轻基础设施项目中地下层融相关的问题提供了指导.
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