A system for reducing the effects of a blast wave includes armor plating configured to face a supersonic blast wave. The armor plating has a surface consisting of alternating tall and short peaks with valleys between the peaks. The peaks and valleys are positioned such that the supersonic blast wave reflects from the side surfaces of the tall peaks as a regular reflection that at least partially suppresses Mach reflection of the supersonic wave caused by the short peaks and the valleys. The surface may also be designed to not trap reflected waves. The valleys can be parabolic shaped to deflect and/or dissipate transonic flow that follows the blast wave front.