FRP reinforcement is a non-corrosive alternative to steel and is gaining popularity for use in reinforced concrete structures exposed to corrosive environments. A major difference between the two reinforcing materials is their behaviour at failure. Steel tends to undergo ductile elongation, while FRP is a brittle material, which ruptures suddenly. Accordingly, while steel reinforced concrete members are generally designed to fail through yielding of the steel, FRP reinforced structures are designed to fail through compressive failure of the concrete. This crushing of the concrete represents plastic deformation. Accurate modelling of the failure of FRP reinforced concrete structures has proven challenging to researchers in the field. However, improvements in the development of material models, among other advances, mean improved accuracy from nonlinear finite element models is now achievable. This paper discusses the challenges of modelling reinforced concrete structures for concrete crushing failure. Results are presented from nonlinear finite element models of FRP reinforced concrete slabs, which were tested to failure and compared to the experimentally derived values.