Effect of transverse clamping force on the tensile behavior of a novel pultruded carbon fiber-reinforced polymer joint: Fatigue test

A novel pultruded carbon fiber-reinforced polymer connection technique for civil engineering that is called pre-tightened single tooth joint has been proven to have good static properties. To investigate the fatigue behavior of the joint, a series of laboratory experiments were carried out. The effects of load level and transverse clamping force on the fatigue behavior were estimated. Experimental results of this work implied that a fatigue life of 1 million as the maximum cyclic load is equal to approximately 83% of the static tensile ultimate bearing capacity. The transverse clamping force could slow down the propagation rate of fatigue crack and significantly improve the fatigue life. Based on the analysis of the hysteresis loops, a small increase in stiffness during the initial loading stage and only about 1%-4% stiffness degradation until fracture were found.