Tensile Properties and Damage Behavior in CFRP ‐Steel Plate Joints With Multiple Bolts

ABSTRACT In steel structure reinforcement engineering, bolted connections represent a crucial method of connection. This study aims to investigate the factors influencing the tensile performance of bolted connections between Carbon Fiber Reinforced Polymer (CFRP) composites and steel plates. This study proposes a finite element (FE) model to predict the ultimate tensile load and progressive damage under various working conditions. The results indicate that bolt type, number of bolts, end distance, and hole pitch are significant factors affecting the connection performance. Bearing failure is identified as the primary failure mode of the joints. The ultimate bearing capacity of protruding head bolt is found to be 17.8%–25.5% higher than that of countersunk head bolt. Increasing the number of bolts significantly enhances the bearing capacity of the joints. For instance, the ultimate load of triple‐bolt joints is 170.9% higher than that of single‐bolt joints. In multi‐bolt joints, varying degrees of bearing failure occur in the CFRP plates due to the complex stress concentration around the bolt holes. As end distance and hole pitch increase, the bearing capacity of the joints increases, while the degree of damage decreases. These findings are validated by the stress distribution observed in the numerical model of CFRP plates under various loading conditions.