Two elementary processes - unaxial compression and creep - were chosen to demonstrate some structural effects in the mechanical behaviour of particulate materials. Six aspects of it - density, grain crushing, angularity, water effect, diffusion and garlandlike creep - were dealt with using firstly theoretical hypotheses and verifying them afterwards by laboratory experiments. Granular clay, silica gel, sand and oat flakes were experimented with. It was shown that the effect of density can be masked by other factors, granulometrical curve may change - due to grain crushing - its shape from Gauss-Laplace to concave form, angularity may radically modify the stress-strain curves, water may initiate hydrocollapses, dry granular material if loaded may be subjected to diffusion and creep may acquire a hybrid form (mixture of diffusion and garlandlike varieties). Various species of nonstandard behaviour have been described. and Obsahuje seznam literatury