重复的冷解周期对粘土机械性能的影响
Haiqiang Jiang1,2, Hongwei Han1,2, Xingchao Liu1,2
1School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin, 150030, China.
Heliyon
|March 12, 2024
概括
克莱·克莱·克莱 (Clay Clay) 是一个
科学领域:
- 地质技术工程 地质技术工程
- 土壤力学 土壤力学
- 土木工程 土木工程是指土木工程.
背景情况:
- 结解周期 (FTC) 显著影响土壤的机械性能.
- 了解这些变化对于寒冷地区的基础设施至关重要.
- 粘土土壤特别容易受到冷解的降解.
研究的目的:
- 在重复的冷解周期下量化粘土机械性质的变化.
- 分析水含量和干燥密度对这些变化的影响.
- 为设计稳定的冷区域工程项目提供数据.
主要方法:
- 实验室实验涉及受控的冷解周期 (0-11周期).
- 三轴测试用于测量凝聚力,切削强度,内部摩擦角度和弹性模量.
- 样品含水量和干燥密度的系统变化.
主要成果:
- 剪切强度,凝聚力和弹性模量随着FTC的增加而下降.
- 内部摩擦角度显示轻微,不显著的增加 (最大4°).
- 在第一次FTC之后,凝聚力退化最为明显.
- 水含量和干燥密度显著影响了所有测试的机械性能.
- 弹性模量随着限制压力而增加.
结论:
- FTCs降低了粘土的关键机械性能,凝聚力最初是最敏感的.
- 土壤中的水含量和干燥密度是影响FTC后行为的关键因素.
- 这些发现指导了在寒冷气候下工程设计和施工,以减轻融效应.
更多相关视频
07:15A Testing Platform for Durability Studies of Polymers and Fiber-reinforced Polymer Composites under Concurrent Hygrothermo-mechanical Stimuli
Published on: December 11, 2014
13.8K
08:59A Freeze-Thawing Method to Prepare Chitosan-Polyvinyl alcohol Hydrogels Without Crosslinking Agents and Diflunisal Release Studies
Published on: January 14, 2020
17.5K
相关概念视频
Frost Action on Concrete
98
Concrete structures in cold climates, such as those along roadsides, can retain moisture. This moisture makes them susceptible to frost-related damage when temperatures fall below freezing. Adding moisture worsens the damage during temperature fluctuations, leading to repeated freezing and thawing. De-icing salts, spread over these structures to melt ice, add to the freeze-thaw cycle, and draw even more moisture into the concrete.
This freeze-thaw cycle primarily causes surface scaling, where...
This freeze-thaw cycle primarily causes surface scaling, where...
98
Brick Durability, Strength, and Appearance
190
Brick durability, strength, and appearance are crucial factors in construction, influencing the choice of bricks for specific applications. The process of freeze-thaw, for instance, significantly affects brick durability. This phenomenon occurs when water absorbed by a brick expands as it freezes, potentially causing damage when it melts and refreezes. Bricks are graded for durability: SW-grade bricks are the most durable, offering high strength and low water absorption, followed by MW-grade...
190
Frost Resistant Concrete
81
Concrete's susceptibility to frost damage during freeze-thaw cycles demands strategic measures to enhance its frost resistance. Employing techniques like air entrainment, adjusting the water-cement ratio, proper curing, and selecting appropriate aggregates are essential.
Introducing microscopic air bubbles into the concrete mix through air entrainment creates small voids that accommodate ice expansion, thereby reducing internal pressures and preventing cracking. The optimal amount of...
Introducing microscopic air bubbles into the concrete mix through air entrainment creates small voids that accommodate ice expansion, thereby reducing internal pressures and preventing cracking. The optimal amount of...
81
Unsoundness of Aggregate due to Volume Change
108
Unsoundness in aggregates due to volume changes is primarily caused by the physical alterations aggregates undergo, such as freezing and thawing, thermal changes, and wetting and drying. Unsound aggregates, when subjected to these changes, result in volume change upon disintegration. This, in turn, contributes to the deterioration of concrete, including scaling, pop-outs, and cracking. Particular types of aggregates, such as porous flints, cherts, and those containing clay minerals, are...
108
Cold Weather Concreting
73
When freshly poured concrete is exposed to freezing temperatures before it has set, the water within the concrete can freeze. This expansion disrupts the setting process, delays chemical reactions necessary for hardening, and increases the volume of pores within the hardened concrete, which weakens its overall structure. If the concrete manages to reach an appreciable strength before it freezes, the damage can be somewhat mitigated.
To counteract the negative impacts of cold weather, ensuring...
To counteract the negative impacts of cold weather, ensuring...
73
Masonry in Cold and Hot Weather Conditions
88
In cold weather, masonry construction requires specific precautions to ensure mortar does not freeze before curing, as this can significantly weaken its strength and watertightness. Mortar temperature should be maintained between 60°F and 80°F to support proper hydration and curing. Below 40°F, mortar water must be heated, but should not exceed 120°F as high temperatures can reduce mortar's compressive and bond strength.
Other key practices include keeping masonry units...
Other key practices include keeping masonry units...
88
