Manufacturing and characterization of polyurethane based sandwich composite structures

Demand has been growing for structural systems utilizing new materials that are more durable and require less maintenance during the service lifetime. In particular, sandwich composite structures attract attention due to many advantages such as light weight, high strength, corrosion resistance, durability and speedy construction. In this study, three designs of glass reinforced composite sandwich structures, namely boxes (web-core W1), trapezoid and polyurethane rigid foam, are fabricated using new generation of two-part thermoset polyurethane resin systems as matrix materials with vacuum assisted resin transfer molding (VARTM) process. The stiffness, load-carrying capacity and compressive strength were evaluated. Core shear, flatwise and edgewise compression tests were carried out for these three models. The mechanical response of three designs of sandwich structures under flexural loading were analyzed using commercial finite element method (FEM) software ABAQUS. The simulation results of flexural behavior were validated by experimental findings.