The deterioration of steel beams presents a severe safety problem in large shipbuilding gantry cranes. The fibre-reinforced polymer (FRP) strengthening technique is commonly used to solve this problem. In current research, the influence of carbon FRP (CFRP) on the flexural strength of large crane steel beams is experimentally studied using scale models of beams to determine the bond interface characteristics of CFRP. In this work, the stress distribution on the bending interface of a main steel beam is investigated under different environmental temperatures. The results show that the bending capacity of long-span steel main beams is improved by CFRP. The experimental results also indicate that insulation and protection of the rubber layer are important factors in the effectiveness of CFRP.

钢梁的劣化在大型造船门式起重机中提出了严重的安全问题。纤维增强聚合物（FRP）增强技术通常用于解决此问题。在当前的研究中，使用梁的比例模型通过实验研究了碳纤维增强塑料（CFRP）对大型起重机钢梁抗弯强度的影响，以确定CFRP的粘结界面特性。在这项工作中，研究了在不同环境温度下主钢梁弯曲界面上的应力分布。结果表明，CFRP改善了大跨度钢主梁的抗弯能力。实验结果还表明，橡胶层的绝缘和保护是影响CFRP有效性的重要因素。