Improving the shear strength of bolted connections in pultruded GFRP using glass fiber sheets

摘要

Pultruded Glass Fiber Reinforced Polymers (PGFRPs) have been increasingly used in the field of engineering construction. In civil engineering structures, mechanical connections such as bolted connections are widely used because they are an easy way to connect the members. However, this kind of connection for PGFRP has low shear strength when the main part of the PGFRPs features unidirectional glass roving, and the shear strength of this part is determined by the shear strength of the matrix. This problem reduces the mechanical performance of the connections. In this study, the strengthening effects of three types of glass fiber sheets (GFSs) (0 degrees/90 degrees, +/- 45 degrees, and a chopped strand mat (CSM)) on PGFRP connections were experimentally investigated under tensile loads. Based on the experimental results, GFSs could remarkably improve the ultimate loads and stiffness of PGFRP connections. Moreover, simple formulas were proposed to evaluate the ultimate loads of single PGFRP-bolted connection reinforced by multiaxial GFSs.