评估由早期干燥引起的混凝土结构裂纹行为,缩小缩小
Mengxi Zhang1,2, Chuntian Lu3, Qiaolin Min2
1State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China.
Materials (Basel, Switzerland)
|January 25, 2025
概括
这项研究对液压水泥砂的早期干燥收缩系数进行了校准,使用实验室实验和中尺度建模. 结果指导了混凝土结构,特别是滚筒压缩混凝土大的裂纹预防.
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:
- 混凝土的早期干燥收缩可能导致裂,影响结构完整性.
- 了解影响收缩的因素对于持久的混凝土建筑至关重要.
研究的目的:
- 对中热波特兰水泥 (MHPC) 和低热波特兰水泥 (LHPC) 砂的早期干燥收缩系数进行校准.
- 开发和验证一个改进的中尺度模型来模拟混凝土的早期干燥收缩.
- 研究环境湿度,水泥类型和总体体积比对混凝土收缩的影响.
主要方法:
- 进行实验室实验以校准收缩系数.
- 开发了一种改进的中尺度建模方法,以在砂,聚合物和ITZ层面模拟混凝土.
- 3D模拟与实验数据进行了验证,在28天后显示的误差不到4.99%.
主要成果:
- 发现LHPC的早期干燥收缩系数约为MHPC的82%.
- 在28天后,环境湿度会影响混凝土收缩到约15毫米的深度.
- 增加环境湿度或总体体积比有效控制早期干燥收缩,并降低质量损失率.
结论:
- 开发的中尺度模型准确地预测了混凝土的早期干燥收缩.
- 这些发现为混凝土结构,特别是滚筒压缩混凝土 (RCC) 中裂纹预防策略提供了理论指导.
- 优化环境湿度和聚合物含量可以减轻水中因收缩引起的裂纹.
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