飞灰/泥基工程地质聚合物复合材料与混凝土之间的粘合性能
Baogui Wang1,2, Hu Feng1, Hao Huang3
1Yellow River Laboratory, Zhengzhou University, Zhengzhou 450001, China.
Materials (Basel, Switzerland)
|June 28, 2023
概括
本研究研究了用于混凝土修复的工程地质聚合物复合材料 (EGC),发现结合强度随着接口粗性和特定纤维增强而提高. 这项研究为与现有混凝土结构挂的EGC建立了债券滑动模型.
科学领域:
- 材料科学与工程 材料科学与工程
- 土木工程 土木工程是指土木工程.
- 结构维修 结构维修
背景情况:
- 混凝土基础设施的维修具有挑战性,需要先进的材料来保持结构寿命.
- 工程地质聚合物复合材料 (EGCs) 对快速结构修复有希望.
- 现有混凝土和EGC之间的接口粘合性能需要彻底调查.
研究的目的:
- 开发具有优异机械性能的EGC用于混凝土维修.
- 评估EGC与现有混凝土基板的粘合性能.
- 分析影响结合强度的微观结构特征.
主要方法:
- 进行了拉伸粘合和单剪接粘合测试,以评估粘合强度.
- 用X射线衍射 (XRD) 和扫描电子显微镜 (SEM) 来进行微观结构分析.
- 基于实验数据开发了一种债券滑坡模型.
主要成果:
- 纽带强度随着接口粗度的增加而增加.
- 聚乙醇 (PVA) 纤维EGC显示了较高的粘合强度,含有较高的飞灰 (FA) 含量和水粘合比.
- 聚乙烯 (PE) 纤维EGC在FA含量变化时,结合强度的变化很小,但在增加水结合比率时,结合强度降低.
结论:
- 接口粗度是EGC混凝土粘合的一个关键因素.
- 纤维类型 (PVA与PE) 显著影响EGC结合性能和对FA含量和水结合比率的反应.
- 微结构分析 (XRD,SEM) 揭示了对C-S-H凝形成和影响机械性能和可塑性的纤维矩阵相互作用的见解.
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