FRP直筋/网格箍-混凝土梁的力学性能试验研究及设计理论

Degradation of concrete structure due to steel corrosion has become a critical problem that seriously threatens the safety of reinforced concrete structures and social economic development. The existing techniques such as retrofitting/strengthening methods or steel protection can achieve certain effects, but they cannot totally solve the issue of steel corrosion. In response to this situation, the project proposed an innovative FRP-concrete composite structure formed by FRP reinforcements and textiles, which will replace the internal steel reinforcements of the concrete structural members. In other words, in this new FRP-concrete beam, longitudinal steel rebars are stead by FRP rebars as well as steel stirrups are stead by FRP textiles. In the project, the investigation on the mechanical properties and design theory of the FRP reinforcements/textiles-concrete beam is carried out. Based on above experimental research and theoretical analysis, the transmission system of bonding stress between FRP and concrete will be revealed; the flexural/shear mechanical properties and mechanism of the new FRP-concrete beam will be systematically analyzed. Furthermore, the flexural/shear strength model will be built, and the corresponding design theory of the innovative FRP-concrete composite beam will also be established. It is expected that the research results will expand and enhance the anti-corrosion theory of concrete structures, as well as new ideas and technical support for the design and construction of concrete structures. This is very necessary and urgent to ensure the service life and economic benefits of the actual project, it also has great practical significance and social benefits.

钢筋锈蚀引发的混凝土结构性能退化已经成为严重威胁结构安全和社会经济发展的严峻问题。现有的结构修复或钢筋防护等技术手段虽能达到一定效果，但并不能根本上解决钢筋锈蚀的弊端。因此，本项目提出一种采用FRP直筋和网格布替代混凝土内部钢筋骨架的FRP直筋/网格箍-混凝土复合梁结构体系，并展开FRP直筋/网格箍-混凝土梁的弯剪力学性能及设计理论研究。通过试验研究和理论分析相结合的方法，揭示FRP直筋-FRP网格箍-混凝土三者界面粘结应力传递体系及协同工作机制；阐明FRP直筋/网格箍-混凝土梁的弯剪力学性能及作用机理；构建FRP直筋/网格箍-混凝土梁的力学计算模型和设计理论。预期研究成果将完善和提升FRP-混凝土力学性能的理论体系和学术水平，对解决钢筋锈蚀问题提供另一种完善解决方案。将有力体现土木工程可持续性发展理念，同时对国家“海洋战略”目标的落实以及海砂资源化利用的推进具有重大的现实意义和社会效益。

钢筋锈蚀引发的混凝土结构性能退化已经成为严重威胁结构安全和社会经济发展的严峻问题。现有的结构修复或钢筋防护等技术手段虽能达到一定效果，但并不能根本上解决钢筋锈蚀的弊端。因此，本项目提出一种采用FRP直筋和网格布替代混凝土内部钢筋骨架的FRP直筋/网格箍-混凝土复合梁结构体系，并展开FRP直筋/网格箍-混凝土梁的弯剪力学性能及设计理论研究。具体进行了FRP复合直筋/网格箍-混凝土梁抗剪性能的实验研究；剪跨比和配箍率对FRP网格箍混凝土梁抗剪性能影响的研究；钢-FRP复合纵筋/FRP条带箍筋梁疲劳剪切性能的研究；FRP局部约束混凝土的力学性能试验研究；FRP-ECC超韧复合材料的拉伸性能试验研究；FRP-橡胶垫块复合加固RC梁的抗剪性能试验研究。通过试验研究和理论分析相结合的方法，揭示FRP直筋-FRP网格箍混凝土三者界面粘结应力传递体系及协同工作机制；阐明FRP直筋/网格箍-混凝土梁的弯剪力学性能及作用机理；构建FRP直筋/网格箍-混凝土梁的力学计算模型和设计理论。在此基础上更进一步的对 预期研究成果将完善和提升FRP-混凝土力学性能的理论体系和学术水平，对解决钢筋锈蚀问题提供另一种完善解决方案。将有力体现土木工程可持续性发展理念，同时对国家“海洋战略”目标的落实以及海砂资源化利用的推进具有重大的现实意义和社会效益。