Evaluation of the blast mitigating effects of fluid containers

• Blast mitigation of water containers and tyres are experimentally evaluated.
• Full water containers shown to mitigate deformation and impulse from blast.
• Air-filled and water-filled tyres shown to mitigate impulse from blast.
• Primary mitigation mechanism of water appears to be momentum extraction.

A series of small scale explosive experiments were performed to evaluate the potential for water filled containers and tyres to mitigate blast loading on armoured vehicles. The experiments compared the effects of an empty water container, a full water container, a full water container at a standoff from the plate, an air-filled tyre, and a water-filled tyre on the momentum transfer and deformation on a steel plate. Both the water containers and addition of water to the tyre reduced the global motion of the plate, but this was only by the same amount as the increase in mass of the system. Hence an equivalent increase in the vehicle mass would provide the same effect. In contrast, the air-filled tyre was able to mitigate the momentum transfer by a larger amount than the increase in mass it provided. The localised deformation experiments found that the use of a water filled container was likely to be more effective at mitigating the deformation of a steel plate than an equivalent increase in mass of the steel. The timescale of the loading indicated that the primary mitigation mechanism of the water was momentum extraction as there was insufficient time for water breakup and evaporation to occur prior to target loading. Further work is still required to confirm the scalability of the results, but this work indicates the potential to use water tanks as part of the blast mitigation system of an armoured vehicle.