酸水合物的微观机制 ((C-S-H) 结冰解周期基于分子动力学
Xiaotian Lin1,2,3, Yulin Wang1,2,3, Henggan Li4,5,6
1Department of Civil Engineering and Architecture, Wuyi University, Nanping, 354300, China.
Scientific reports
|July 23, 2025
概括
分子动力学模拟显示,-酸盐-酸盐 (C-S-H) 密度在结解周期中发生显著变化. 更高的温度差异和更快的速度加剧了这些变化,影响了材料的耐用性.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 化学 化学 化学
背景情况:
- 酸水合物 (C-S-H) 是基于水泥的材料中的关键成分.
- 了解C-S-H在结解等环境压力因素下的行为,对于材料的耐用性至关重要.
- 冰解循环可以导致混凝土结构的退化和故障.
研究的目的:
- 为了研究C-S-H在模拟的冷解周期中的微结构演变.
- 量化温度变化和循环速率对C-S-H密度和分子动态的影响.
- 在水泥材料中建立冷解失效机制的理论基础.
主要方法:
- 用分子动力学 (MD) 模拟来在融条件下建模C-S-H.
- 模拟追踪了C-S-H密度,分子运动和系统压力的变化.
- 参数变化包括温度差异,温度变化率和C-S-H组成 (C/S和W/S比).
主要成果:
- 在冷过程中,C-S-H密度增加,在解过程中减少.
- 较大的温度差异导致更大的密度波动和更明显的分子运动.
- 温度上升/下降率的增加会增加密度变化率和系统压力.
- 较高的与 (C/S) 和水与 (W/S) 比率在冷解周期中增强了原子运动.
结论:
- 结解循环会诱导C-S-H的显著微观结构变化,影响其密度和分子流动性.
- 这些变化的强度受到温度梯度,循环速率和材料的化学成分的直接影响.
- 这些发现为水泥材料的冷解降解机制提供了关键的理论见解,有助于开发更有弹性的建筑材料.
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