Chemical ageing effects on the ply and laminate strength of a filament wound cross-ply GFRP

This work presents a numerical approach to multi-routines based on experiments, and, with a target to analyse strength of a cross-ply glass fibre reinforced plastics (GFRP) composite after immersion in sulphuric acid solution under pressure (5% H2SO4 solution, 95 degrees C, 15 bar). Two alternative vinyl ester resins (bisphenol A digly-cidyl ether and epoxy phenol novolac) were investigated. After 0.5, 1, 1.5 and 2 years of conditioning, the specimens were mechanically tested. The mull-scale definition of the material system and its virtual conditioning were performed in a finite element (FE) model. The Hashin 3D failure criterion was implemented by coding the UMAT subroutine when using the Abaqus software. The experimental results demonstrated better performance of the bisphenol A vinyl ester resin-based GFRP when a thin barrier layer is used. The numerical results indicated that the shear strength property was the most susceptible at weak zones to present a tendency for degradation after one year of conditioning.