Аннотация:The paper studies the process of crack growth in a material with gas-filled pores during unloading from external compressive stresses. The variant of directional unloading is considered when a system of parallel cracks oriented perpendicular to the direction of the least compression is formed, and uniform all-round unloading when a system of randomly directed cracks is formed. The effective elastic characteristics of the material for these two cases are estimated. Regularities of crack growth in both cases are revealed depending on the porosity of the material.