Acta Scientiarum Polonorum

Thin-walled structures have considerably become popular due to their light weight, easy installation and simple manufacturing technology. However, they are liable to the loss of stability (which occurs locally or generally) and therefore, it often happens that the bearing capacity of a structural component is determined by buckling or by the after-buckling state. Regarding that, both the proper assessment of deformation as well as its measurement have become a crucial task that needs to be performed before the designing phase of such structures. The main goal the authors intended to achieve was to perform some preliminary laboratory tests that would be helpful to assess the possibility of using geodetic positioning techniques for measuring horizontal displacements of steel sections undergoing global and local stability loss under axial compressive force.