Small Scale Models Subjected to Buried Blast Loading Part II: Frame Accelerations with Hulls and Additional Mitigation Methods

Small scale models representing key vehicle structural elements, including bottom-mounted hulls and other relatively simple strategies for blast mitigation, have been manufactured and subjected to a range of buried blast loading conditions. By varying surface stand-off distance and depth of burial for several hull and structure configurations, the response of full-scale vehicle frames has been quantified through input-scaling. High speed stereo-vision and surface-mounted accelerometers are used to measure accelerations during the blast loading process. The maximum vertical acceleration and the Head Injury Criterion (HIC₁₅) at selected frame locations are quantified as metrics to assess the severity of the blast event. Results show that (a) inverted and standard V-shaped hulls provide essential blast mitigation capability, reducing the maximum frame accelerations over 100X, with similar reductions also measured for HIC₁₅, (b) stiffened frame structure locations experience substantially lower levels of acceleration and HIC₁₅ than measured previously on the floorboard at the expense of decreased damping of structural vibrations and (c) hull coating systems such as polyurea provide significant additional mitigation, though at the expense of increased overall weight.