Reinforced concrete beams coated with fiberglass-reinforced polymeric profiles as partial substitutes for the transverse reinforcement

abstract: The use of GFRP (Glass Fiber Reinforced Polymers) structural profiles in the construction sector is growing due to their attractive properties, such as high mechanical strength and durability in aggressive environments. With this, it is necessary to conduct studies that deepen the knowledge about the performance of these materials in structural applications. Therefore, this work aims to analyze the mechanical performance of reinforced concrete beams coated with GFRP profiles, in comparison to reinforced concrete beams, by analyzing groups with different spacing between transversal reinforcement. In all groups there was no change in the longitudinal reinforcement, and the D and Q groups were, respectively, made up of transverse reinforcement spaced twice and quadruple the one calculated for the reference beams, and presented the GFRP profiles in their constitution. All beams were tested at four-point bending, and strain gauges were installed in one of the beams of each group studied. The results obtained in the tests showed an increase in strength of 83.67% in the beams of group D, and 79.91% for group Q, in relation to the references. The analysis of longitudinal deformations made it possible to verify increases in stiffness and the moment of cracking in composite beams. Thus, based on this study, the composite structures studied may constitute future solutions for constructions exposed to aggressive environmental conditions, in order to increase their durability and also to contribute to the design of such structural elements with lower reinforcement rates.

摘要：玻璃纤维增强聚合物（Glass Fiber Reinforced Polymers，GFRP）结构型材在建筑领域的应用正日益增长，这得益于其优异的性能，如较高的机械强度以及在侵蚀性环境下的耐久性。为此，亟需开展相关研究以深化对这类材料在结构应用中性能表现的认知。
本研究旨在通过设置不同横向钢筋间距的试验组，对比分析包覆GFRP型材的钢筋混凝土梁与普通钢筋混凝土梁的力学性能。所有试验组的纵向钢筋配置均保持一致；其中D组与Q组分别采用了基准梁计算间距两倍、四倍的横向钢筋，且两组均内置GFRP型材。所有梁试件均开展四点弯曲试验，并在每个试验组的一根梁上安装了应变片。
试验结果表明，相较于基准梁，D组梁的强度提升83.67%，Q组梁提升79.91%。对纵向变形的分析证实，组合梁的刚度与开裂弯矩均得到提升。综上，本研究涉及的组合结构可作为未来侵蚀性环境中建筑结构的解决方案，既能提升结构耐久性，也可为此类结构构件采用更低配筋率的设计提供参考。