The disclosure provides a shock absorbing layer comprised of one or more shock absorbing cells, where a shock absorbing cell is comprised of a cell interior volume containing a plurality of hydrogel particles and a free volume, and where the cell interior volume is surrounded by a containing layer. The containing layer has a permeability such that the hydrogel particles when swollen remain at least partially within the cell interior volume when subjected to a design shock pressure wave, allowing for force relaxation through hydrogel compression response. Additionally, the permeability allows for the flow of exuded free water, further dissipating wave energy. In an embodiment, a plurality of shock absorbing cells is combined with a penetration resistant material to mitigate the transmitted shock wave generated by an elastic precursor wave in the penetration resistant material.
The United States Government has rights in this invention pursuant to Contract No. DE-AC07-05ID14517, between the U.S. Department of Energy (DOE) and Battelle Energy Alliance, LLC.