Experimental investigation and analytical modeling of dry glass fiber braided sleeves for tensile behaviour

Abstract

In this work, the longitudinal tensile strength of a dry unimpregnated glass fibre triaxially braided fabric was studied. The braided fabric was fabricated in the form of sleeves by modifying a vertical biaxial braiding machine. In order to retain the braid architecture and tension in the fibres, the ends of the sleeves have to be impregnated with epoxy resin. The effect of the length of the epoxy resin impregnation at the ends was studied. Tensile tests on three different braid angles, i.e. 30°, 45° and 60° specimens were conducted. The tests were also simulated in ABAQUS and the results obtained were compared with the experimental output. A numerical model was developed and executed in MATLAB to find the mechanical properties of the dry braided fabric. It was observed that with no or less epoxy impregnation at the ends, the dry braided fabric would take more load as compared to its unidirectional counterparts. Also, the tensile strength in terms of the maximum load of the braided glass specimen decreases with increase in braid angle.