实验和3D模拟研究冷结合的飞轻质聚合混凝土的机械性能,暴露在不同的高温下
Shuai Xu1,2, Pengfei Fu1, Yanyan Liu3
1School of Civil Engineering, Jilin Jianzhu University, Changchun 130118, China.
Materials (Basel, Switzerland)
|November 13, 2025
概括
轻质混凝土中的冷结合飞灰聚合物 (LWC-CB) 与普通混凝土相比,在500°C以下显示出优越的强度保留. 高温后的损伤从聚合物转移到砂和接口区域.
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.
- 混凝土技术 混凝土技术
背景情况:
- 使用冷结合 (CB) 飞灰聚合物的轻质混凝土 (LWC) 为天然聚合物提供了一个环保的替代品.
- 了解LWC-CB的高温性能对于其结构应用至关重要.
研究的目的:
- 研究LWC-CB在暴露于高温后的机械性能和损伤机制.
- 为了比较LWC-CB与普通混凝土的高温性能.
- 开发和验证用于预测LWC-CB行为的数值模型.
主要方法:
- 在10°C至600°C的温度下对LWC-CB标本进行立方压缩试验.
- 数字图像相关性 (DIC) 用于监测表面变形.
- 开发和验证3D中大尺度和均化模型.
主要成果:
- 在500°C以下,LWC-CB比普通混凝土保持约6%的强度.
- 故障模式从环境温度下的聚合物控制切割转换为高温下的砂/ITZ损坏.
- 数字模型准确地预测了实验结果,在10°C时的偏差低于15%,加热后的偏差低于3%.
结论:
- 在高温后,LWC-CB表现出有前途的机械性能.
- 由于微裂纹和热不匹配,高温会导致砂和界面过渡区 (ITZ) 内的损坏.
- 经过验证的数值模型为分析LWC-CB热力学行为提供了可靠的工具.
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