Shear behavior of multi-axial fiber reinforced composite sandwich structures with pultruded profile core

In this paper, a new sandwich structures using multi-axial glass fiber reinforced polymer (GFRP) as face sheets and webs while pultruded profile as core was proposed, which intended to be used in engineering fields such as trestle board, bridge deck, emergency road deck. The shear behavior of the multi-axial fiber reinforced composite sandwich structures with pultruded profile core was investigated, and the failure modes, load-deflection behavior and load-strain relationships were obtained and compared under three points bending test. The results showed that all the sandwich structures had obvious omen before failure, and the final failure modes and shear bearing capacities of the sandwich structures varied with web thickness, face sheet thickness and the type of fiber cloth. Among them, increasing the thickness of the surface layer of sandwich structure is the most obvious way to improve the shear capacity, which can increase the shear capacity by more than 40 %. Formulas to calculate the stiffness, the deflection and the ultimate bearing capacity were derived and proved appropriate. Meanwhile, the proposed pultruded profile sandwich structure was proved can be used as highway bridge deck.