Abstract <p>The initial boundary value problem of the impact of a shock pulse falling from a gas into a powdered medium saturated with a gas-liquid mixture is solved numerically. The cases of pulse reflection from a layer of bubbly liquid and from a porous medium saturated with a gas-liquid mixture are analyzed. The influence of the parameters of the powder layer on the initiation of waves in the powdered medium is investigated. It is established that in a powdered medium filled with a gas-liquid mixture, the main contribution to the total stress is made by the pressure of the pore gas-liquid mixture.</p>