DESIGN OF SLENDER RC COLUMNS ACCORDING TO EUROCODE 2

We have analyzed the application of the Eurocode rules for calculating single-storey buildings which need columns of significant slenderness. The results of simplified calculations, i.e. based on the concept of isolated members design, have been compared with the exact calculations, i.e. based on nonlinear analysis of the whole structural system. We have concluded that assuming the same effective length l(0) for cantilevers (i.e. l(0) = 2l(col)) may in some cases lead to obtaining results which are inconsistent with the exact calculations. The problem of calculating the effective length mostly presents itself when using the simplified method. In the exact method it is not required to determine the effective lengths. This is why it is advisable while designing to use the exact method based on second order analysis and takes into account the nominal stiffness. For very slender columns it is also important to take into account the influence of soil flexibility on the increase of bending moments resulting from foundation rotation.