在冷解周期期间,污染土壤的固化/稳定通过聚氨:机械,浸和微观结构的特征
Qiang Ma1,2, Pangkun Zheng2, Junjie Chen2
1School of Architectural Engineering, Huanggang Normal University, Huanggang 438000, China.
Materials (Basel, Switzerland)
|March 28, 2024
概括
聚氨有效地固化污染的土壤在结的地区,防止浸出和冰晶的扩张. 这种聚合物稳定了土壤的结冰解周期,为环境修复提供了可行的解决方案.
科学领域:
- 环境科学 环境科学
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
背景情况:
- 季节性结土壤中的污染对环境构成风险.
- 聚氨 (PU) 显示出由于其耐用性而具有土壤稳定性的潜力.
- 关于PU在稳定寒冷地区的污染土壤的机制的研究有限.
研究的目的:
- 研究聚氨在季节性结地区污染土壤固化的机制.
- 分析PU在结解周期下的有效性.
- 探索孔隙结构和功能组在PU介导的土壤稳定中的作用.
主要方法:
- 分析不同PU含量和结解周期的出水行为.
- 微观表征技术用于研究孔隙结构和功能组.
- 评估PU与离子和土壤矩阵的相互作用.
主要成果:
- 在冷解周期后,PU有效地抵抗土壤恶化和二次泄露.
- 离子的化度仍然低于法规限制 (1.09 mg/L).
- 聚烯抑制冰晶的膨胀,并通过物理封装和复合凝固.
结论:
- 聚氨是一种可行的材料,用于在季节性冷地区固化污染的土壤.
- 在PU中的胺基,甲基和异酸盐群是复合的关键.
- 聚烯提供了强大的屏障,防止泄露,即使在结解损坏后.
相关概念视频
Frost Action on Concrete
97
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...
97
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
Cold Weather Concreting
72
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...
72
Waterproofing and Anti-Bacterial Admixtures in Concrete
78
Concrete's susceptibility to water absorption is due to the capillary action within the pores of its hydrated cement paste. This action draws water in, creating the need for waterproofing admixtures to prevent such penetration. The efficacy of these admixtures is contingent upon the water pressure, with variations arising from different conditions such as rain, capillary rise, or hydrostatic pressure in structures intended to hold water.
Waterproofing admixtures render concrete hydrophobic,...
Waterproofing admixtures render concrete hydrophobic,...
78
Recrystallization: Solid–Solution Equilibria
1.1K
Recrystallization is a purification technique used to separate impurities from solid compounds. In this technique, no chemical reactions occur. Instead, it exploits physical properties only, specifically, the solubility differences between the desired compound and impurities, either at a single temperature or at different temperatures, and under other selected conditions. The solid-solution equilibrium (solubility equilibrium) of each component in the solution represents a binary phase...
1.1K
Corrosion of Reinforcement
181
The corrosion of steel reinforcement within concrete is a process influenced by the material's inherent properties and external factors. The high pH level of around 13, provided by calcium hydroxide present in concrete, initially protects the steel reinforcement by promoting the formation of a passive iron oxide layer on its surface.
However, over time and under certain conditions like carbonation, chloride ingress, and cracking this protective state can be compromised. Steel has areas with...
However, over time and under certain conditions like carbonation, chloride ingress, and cracking this protective state can be compromised. Steel has areas with...
181


