树脂预浸技术提升CFRP-混凝土界面力学性能研究

doi:10.19936/j.cnki.2096-8000.20250228.015

摘要/Abstract

摘要： 碳纤维增强复合材料(CFRP)已被广泛应用于混凝土结构加固工程中,但CFRP-混凝土界面常因为表层混凝土薄弱区的过早破坏而影响加固效果。鉴于此,本文采用不同浓度树脂预浸(Resin Pre-Coating,RPC)溶液对混凝土表面进行预浸处理以增强其表层力学性能。分析并阐明了体积浓度为10%~50%的RPC溶液处理混凝土表面对CFRP-混凝土界面承载力、界面应力分布及黏结-滑移关系等的影响规律及其增强机理。结果表明,RPC处理可以使环氧树脂有效渗入混凝土表层的微裂缝和孔洞,固化后的环氧树脂与混凝土之间形成机械咬合作用,能有效提高CFRP-混凝土界面力学性能,改善界面破坏形式。针对本文试验的C40混凝土,采用体积浓度为30%的RPC溶液处理,可以有效避免混凝土过早破坏,使胶层强度得到充分利用,与未经RPC处理的对照组相比,界面极限承载力提高了78.4%,界面抗剪强度和界面剪切断裂能分别提高了71.1%和3.66倍。

关键词: 树脂预浸技术(RPC技术), 表面处理, 界面增强, CFRP-混凝土界面, 外贴法, 复合材料

Abstract: Although carbon fiber reinforced composites (CFRP) are widely used in strengthening of concrete structures, the strengthening effectiveness is often reduced, primarily due to premature damage in the weaker sub-surface of concrete. To address this issue, the study employed resin pre-coating (RPC) solutions with different concentrations to treat the concrete surface and improve its mechanical properties. The effects of RPC treatment with volume concentrations from 10% to 50% on the load-carrying capacity, interfacial shear stress distribution and bond-slip relationship were analyzed. Besides, the enhancing mechanisms were elucidated. The results demonstrated that the epoxy resin can efficiently penetrate into the microcracks and voids in the concrete sub-surface based on the RPC treatment. The cured epoxy resin created interlocking action between the epoxy and concrete, effectively enhancing the mechanical properties of the CFRP-concrete interface and modifying the failure mode. For the C40 concrete tested in this paper, the RPC treatment with the volume concentration of 30% effectively prevented premature concrete destruction, maximizing the adhesive layer’s strength. This resulted in a 78.4% increase in the load-carrying capacity compared to the control group with no RPC treatment. Additionally, the interfacial shear strength and interfacial shear fracture energy increased by 71.7% and 3.66 times, respectively.

Key words: resin pre-coating, surface treatment, interfacial reinforcement, CFRP-concrete interface, externally bonding method, composites

中图分类号:

TB332

房恩惠, 杨树桐, 庞瑞阳, 孙忠科, 兰天. 树脂预浸技术提升CFRP-混凝土界面力学性能研究[J]. 复合材料科学与工程, 2025, 0(2): 117-128.

FANG Enhui, YANG Shutong, PANG Ruiyang, SUN Zhongke, LAN Tian. Improvement of CFRP-concrete interfacial performance by resin pre-coating method[J]. COMPOSITES SCIENCE AND ENGINEERING, 2025, 0(2): 117-128.

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