The paper presents the results of experiments concerned with the deformations of a bulk solid during the silo emptying process. Measurements with application of the PIV (Particle Image Velocimetry) technique were performed, both in the case of a silo with mass flow and one with funnel flow. Tests were performed for different initial conditions: density and wall roughness. During the experiments only the part of the bulk solid near the silo wall was taken into account; internal displacement of the bulk solid did not influence the experiments results. Localizations along the silo walls and created at the width of the silo at the flowing material were detected and described. The thickness of the localisations in the form of shear zones was discussed.