Improvised Explosive Devices (IEDs) and mines pose significant threat to military ground vehicles and soldiers in the field. Due to the severity of the forces exerted by a blast, ground vehicles may undergo multiple sub-events subsequent to an explosion, including local structural deformation of the floor, gravity flight and slam-down. The current method of choice to simulate the effect of a shallow-buried IED or mine on a Lagrangian vehicle model, is a fluid-structure interaction with the environment modelled with an Eulerian formulation (explosive, ground, air) [1]. This method, also called Arbitrary Lagrangian-Eulerian (ALE), is more expensive and involved than pure structural methods (usually pressure loads applied to the vehicle surface). However, it allows for taking into account the effect of the shape, type and size of the charge and the soil characteristics on the impulse transmitted to the vehicle. Three approaches are proposed to reduce the analytical simulation time while maintaining the highest level of accuracy throughout the full blast and subsequent sub-events. The tradeoffs between the approaches are detailed in this paper.