数字研究对聚合物湿度对混合过程的影响
Guodong Cao1, Sheng Xie1, Daiqiang Deng1
1College of Civil Engineering, Xiangtan University, Xiangtan 411105, China.
Materials (Basel, Switzerland)
|February 24, 2024
概括
在混凝土混合中,将少量水分添加到聚合物中,可以在最初改善均性. 然而,随着混合时间的延长,这种效果会减弱,显示出湿度.
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.
- 计算力学 计算力学 计算力学
背景情况:
- 聚合物湿度显著影响混凝土混合动力和均性.
- 了解不同湿度条件下的粒子相互作用对于优化混凝土生产至关重要.
- 现有的模型往往简化或忽略了液体桥力在聚合物相互作用中的作用.
研究的目的:
- 研究聚合物湿度对沙子和石头混合均性的影响.
- 为了建立湿度含量和凝聚性接触模型参数之间的功能关系.
- 为了验证离散元件方法 (DEM) 适用于模拟潮湿聚合物的混合的适用性.
主要方法:
- 使用离散元素方法 (DEM) 模拟聚合物混合.
- 在干粒子相互作用中使用赫茨-明德林模型.
- 应用了线性凝聚力模型,结合了液体桥力,用于湿粒子相互作用.
- 建立了水分含量和线性凝聚性接触模型参数之间的功能关系.
主要成果:
- DEM是一种可行的数值方法,用于模拟聚合物混合过程.
- 线性凝聚力模型适用于卵石的水分含量 (0-0.75%) 和沙子的水分含量 (0-10.9%).
- 低水分含量最初会提高混合均性 (较低标准偏差),但在延长混合时间时没有显著影响.
结论:
- 少量的水分可以提高混凝土聚合物的初始混合均性.
- 湿度对混合均性的影响取决于混合持续时间.
- 这些发现提供了优化混凝土混合工艺的见解,通过控制聚合物的水分.
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