混凝土板的早期破裂行为与GFRP增强材料的混凝土板
Hossein Roghani1, Antonio Nanni1, John E Bolander2
1Department of Civil and Architectural Engineering, University of Miami, Coral Gables, FL 33146, USA.
Materials (Basel, Switzerland)
|August 12, 2023
概括
玻璃纤维增强聚合物 (GFRP) 强化有效地限制了早期的塑料收缩裂在混凝土板块中. 虽然最初的裂形成不受影响,但GFRP随着时间的推移限制了裂宽度.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 建筑技术 建筑技术 建筑技术
背景情况:
- 早期的混凝土裂对结构完整性和使用寿命产生重大影响.
- 塑料收缩裂变是混凝土板的关键问题,受到环境因素和材料特性的影响.
- 玻璃纤维增强聚合物 (GFRP) 越来越多地被用作在混凝土结构中替代钢铁的增强材料.
研究的目的:
- 调查GFRP增强在缓解早期塑料收缩裂纹在混凝土板中的有效性.
- 为了在受控的塑料收缩条件下比较GFRP钢筋与钢筋和非钢筋混凝土的性能.
- 了解GFRP条和混凝土之间的早期年龄债券特征对裂发展的影响.
主要方法:
- 在受控的蒸发速度下对9个小型混凝土板样本进行实验测试.
- 获取裂发展图像以估计裂宽度.
- 对于GFRP和钢筋钢筋的早期结合测试.
- 对混凝土强度和设置时间的透阻力测试.
- 使用沃罗诺伊细胞格子模型进行三维数值建模.
主要成果:
- 与钢材相似的GFRP钢筋,在塑料收缩过程中没有影响裂开始的时间或最初的裂开口.
- 早期结合测试揭示了在干燥条件下钢筋和混凝土之间的相互作用.
- 数字模拟,结合测量结合性质,证实GFRP钢筋限制裂的发展,但不能完全阻止它.
- 裂宽度估计表明,与对照样本相比,GFRP增强物减少了裂严重性.
结论:
- GFRP钢筋在控制和减少早期塑料收缩裂纹在混凝土板上的严重性方面表现出有效性.
- 该研究提供了关于GFRP在早期混凝土裂解中的性能的宝贵数据,支持其在建筑中的应用.
- 进一步的研究可以探索GFRP增强策略的长期性能和优化,以加强裂纹控制.
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