An Experimental Study on the Shear Performance of a CFRP–Steel Composite Component Bushing Bolt Connection

Carbon Fiber Reinforced Polymers (CFRPs) are extensively utilized in civil engineering and other domains due to their exceptional mechanical properties. Integrating CFRPs with steel presents an approach to structural design, characterized by enhanced load-bearing capabilities and extended service life. Static tensile and hysteretic tests were employed to examine the influence of the bolt diameter and steel plate thickness on the shear resistance of component. The results indicate that under monotonic loading, the load–displacement curves for each component undergo three distinct phases: the linear stage, damage evolution stage, and failure stage, ultimately leading to a bolt pull-off failure in all six groups of components. Under cyclic loading, the component with a 1.5 mm thick steel plate and a 4.6 mm diameter bushing bolt experienced bolt shear failure, primarily caused by the increased steel plate thickness, which enhanced the component’s load-carrying capacity, ultimately leading to the overloading and failure of the M4 bolt. The other five groups of components experienced pull-off failures. The hysteresis curve analysis revealed that enhancements in steel plate thickness and bolt diameter improve the hysteresis behaviour of the connections. However, there was a significant reduction in the strength degradation coefficient and hoop stiffness, which decreased to approximately 55% and 40% of their initial values, respectively.