Abstract In this paper, we analyse the surface crack growth in the Fibre-Reinforced Polymer (FRP) reinforced steel plates subjected to tension by means of the finite element (FE) method. Following the experimental study, a three-dimensional FE model is developed to evaluate the Stress Intensity Factor (SIF) of the surface crack, and the crack growth rate is calculated by using the Paris’ law. Then the FE model is validated by the experimental results. Afterwards, on account of the validated FE model, a parametric study is developed in order to guide the optimization design of FRP reinforcement accounting for different reinforcing schemes and multiple influential parameters. The results indicate that the single-side FRP reinforcement on the cracked surface is the most efficient method, owing to the generated out-of-plane bending moment. In addition, the optimum bond length and number of layers are indicated. Besides, surface crack growth is sensitive to the influential parameters including aspect ratio of the surface crack and crack dimension, while less sensitive to the Carbon-FRP (CFRP) tensile modulus, and the adhesive thickness. The analysis is of instructive value to facilitate the application of FRP reinforcement on the surface cracked metallic structure repairing domain.

中文翻译：

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FRP增强钢板受拉表面裂纹扩展的数值研究

摘要 在本文中，我们通过有限元（FE）方法分析了受拉的纤维增强聚合物（FRP）增强钢板的表面裂纹扩展。根据实验研究，开发了三维有限元模型来评估表面裂纹的应力强度因子（SIF），并使用巴黎定律计算裂纹扩展速率。然后通过实验结果验证有限元模型。然后，基于经过验证的有限元模型，开展了参数研究，以指导针对不同加固方案和多个影响参数的 FRP 加固优化设计。结果表明，由于产生了平面外弯矩，裂纹表面上的单面 FRP 加固是最有效的方法。此外，指出了最佳键长和层数。此外，表面裂纹扩展对包括表面裂纹纵横比和裂纹尺寸在内的影响参数敏感，而对碳-FRP（CFRP）拉伸模量和粘合剂厚度不太敏感。该分析对促进FRP加固在表面裂纹金属结构修复领域的应用具有指导价值。