Failure analysis of an ice floe impacting on a fixed arctic offshore structure has been carried out. The ice floe has been idealized to be an edge-loaded, inertia-driven, thin circular disk made of an elastic-brittle material obeying the Drucker-Prager failure envelope. The location of failure initiation and the associated load have been calculated. Fracture mechanics of global splitting of the floe by crack propagation has been presented. An appropriate limit analysis solution of the problem has also been developed. A comparison of the various results developed in the paper leads to some interesting conclusions.