部分由工程混凝土复合材料 (ECC) 组成的混合钢筋混凝土梁的可用性和柔性行为
Ahmed A Radwan1, Ahmed Ghallab2, Ahmed M Farghal Maree2
1Department of Structural Engineering, Ain Shams University, Cairo, Egypt. ahmed.alaa@eng.asu.edu.eg.
Scientific reports
|August 21, 2025
概括
这项研究研究了用玻璃纤维增强聚合物 (GFRP) 或混合钢-GFRP条和工程水泥复合材料 (ECC) 增强的混凝土梁. 结果显示,ECC提高了光束性能,U形配置提高了柔性.
科学领域:
- 土木工程
- 材料科学
- 结构工程
背景情况:
- 混凝土梁的钢筋腐蚀是一个重要问题,特别是在恶劣的环境中.
- 玻璃纤维增强聚合物 (GFRP) 条为钢提供了耐腐蚀的替代品.
- 工程混凝土复合材料 (ECC) 和混合增强材料 (钢GFRP) 可以提高混凝土梁的强度和可用性.
研究的目的:
- 仅使用GFRP条或使用部分工程水泥复合材料 (ECC) 的混合钢-GFRP条来研究混凝土梁的屈曲和可塑性.
- 评估ECC配置 (不同厚度和U形件) 对梁行为的影响.
- 评估这些复合梁的偏移预测方程的准确性.
主要方法:
- 建造了七个梁:一个控制梁和六个部分ECC梁用GFRP或混合增强.
- 样本经过四点曲测试,分析裂纹图案,动量-张力和动量-曲率关系.
- 根据实验数据对ACI 318-19,CSA S806-12和ACI 440.1R-15的偏差方程进行了评估.
主要成果:
- 在紧张区域的较厚的ECC层改变了裂分布,度和能量吸收.
- 通常情况下,U型ECC配置会增加性指数.
- 波纹表面施工技术改善了接口剪切转移,并防止了粘合故障.
- ACI 318-19和CSA S806-12的偏移方程式与实验结果相对应,而ACI 440.1R-15显示了差异.
结论:
- 部分使用ECC与GFRP或混合增强提供了一个可行的解决方案,以减轻混凝土梁的腐蚀问题.
- ECC配置显著影响光束性能,U形设计增强了柔性.
- 特定的施工技术可以改善混合梁的界面粘合.
- 现有的曲率预测代码需要精细化,以准确评估ECC钢筋混凝土梁.
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