Effect of eccentricity on the behavior of pultruded FRP bolted joint

摘要

Fibre reinforced polymer (FRP) composites are becoming an alternative choice for the development of structural truss system. It takes advantage of the unidirectional properties of fibre composites as truss members are subjected mostly to axial forces.The typical connection used for this type of structure is a bolted joint. This paper presents the behavior of closed section (100 mm x 75 mm x 5.25 mm) of pultruded glass FRP (GFRP) composite with bolted joint under eccentric loading. The T-joint component of the truss was designed with 1-bottom chord (1B) to simulate the eccentric condition and compared with a T-joint with 2-bottom chords (2B) for concentric loading. Stainless steel bolts (all-threaded) were used and tightened with a torque of 25N.m. The joint failed due to local punching shear at one side of the connection area due to eccentric effect and a load less than half that of the joint with concentric loading. It was found that the testing specimen with eccentricity experienced local damaged which had reduced its joint capability almost twice than that specimen without eccentricity