在寒冷地区的运河结构下方的泥土和膨胀土壤的机械性能对比研究
Rui Zhu1,2,3, Wei Xing1, Feng Zhou1
1School of Transportation Engineering, Nanjing Tech University, Nanjing, 211816, China.
Heliyon
|August 8, 2024
概括
粘土土在潮湿-干燥-结-解周期下表现出稳定的机械性能,使其成为寒冷地区膨胀土壤的有效替代品. 广的土壤经历了显著的财产退化,特别是在前三个周期内.
科学领域:
- 地质技术工程 地质技术工程
- 土壤力学 土壤力学
- 寒冷地区工程 寒冷地区工程
背景情况:
- 膨胀的土壤在寒冷地区带来了挑战,因为水分和温度波动导致的体积变化.
- 粘土土壤经常被用作填充材料,以取代有问题的膨胀土壤.
- 了解环境循环对土壤行为的影响对于基础设施稳定至关重要.
研究的目的:
- 研究湿-干燥-冷-解 (WDF) 周期对泥土和膨胀土壤的机械性能的影响.
- 为了比较粘土土壤在循环环境压力下的耐用性和稳定性与膨胀土壤.
- 提供关于泥土土壤适合于寒冷气候中作为扩张土壤的替代品的见解.
主要方法:
- 进行了实验室测试,以模拟湿-干燥-冷-解周期.
- 测量了包括弹性模量,故障强度,凝聚力和内部摩擦角度在内的机械性能.
- 分析了微观结构,表面裂和粒径分布,以了解降解机制.
主要成果:
- 在7个WDF循环后,粘土土的机械性能出现了最小的降解 (降低8.9%-12.0%).
- 扩展性土壤在7个WDF循环后显示了机械性能显著降低 (17.6%-37.0%下降).
- 扩展性土壤中超过90%的机械性能减弱发生在前三个WDF周期内,伴随着显著的微观结构损伤.
结论:
- 与广的土壤相比,粘土土表现出优越的稳定性和对WDF循环的抵抗力.
- 这些发现支持使用泥土土壤作为寒冷地区运河结构下方膨胀土壤的有效和稳定的替代品.
- 广土壤的快速降解凸显了在地质工程设计中考虑环境循环效应的重要性.
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