对制造砂混凝土的收缩预测模型的分析和纠正
Wei Fan1, Yang Wei1,2, Jiyang Yi1
1College of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China.
Materials (Basel, Switzerland)
|August 28, 2025
概括
制造砂混凝土 (MSC) 的收缩不同于天然砂混凝土. 结合工业砂的新模型提高了绿色建筑的收缩预测准确度.
科学领域:
- 土木工程
- 材料科学
- 可持续建设
背景情况:
- 天然沙子的枯竭需要制造沙子等替代材料.
- 与传统混凝土相比,制造的砂混凝土具有不同的收缩行为.
- 现有的收缩模型不充分考虑制造砂的特性,限制了准确性.
研究的目的:
- 评估MSC的经典收缩预测模型.
- 确定现有模型在制造砂的特性方面的局限性.
- 为准确的MSC收缩预测开发增强型号.
主要方法:
- 使用实验MSC数据对ACI 209,CEB-FIP 2010,B3和GL 2000模型进行系统评估.
- 影响收缩的制造砂的特性 (颗粒形态,分级,石粉) 的分析.
- 开发一种基于非线性回归的校正函数,其中包含制造砂的含量.
主要成果:
- 由于忽视了制造砂的特性,B3和CEB-FIP 2010模型显示了显著的预测差异.
- 开发的校正功能,使用制造砂含量,增强了ACI 209和GL 2000模型.
- 经过修改的模型显示MSC在所有替换率上都提高了适配性能和预测稳定性.
结论:
- 经典的收缩模型需要重新校准才能准确地预测MSC.
- 制造砂含量是改善收缩模型的关键变量.
- 改进的模型为预测MSC缩提供了可靠的框架,支持可持续建筑.
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