Bearing Capacity of Slender Concrete Columns

The European standard for the design of concrete structures using nonlinear methods contains a deficit in global reliability for cases when concrete columns fail due to a loss of stability before reaching the design resistance in the critical cross-sections. A buckling failure is a brittle failure which occurs without warning, and the probability of its formation is markedly influenced by the slenderness of the column. The calculation results presented herein are compared with the results from experimental data. The paper aims to compare the global reliability of slender concrete columns with a slenderness of 90 and higher. The columns are designed according to the methods stated in EN 1992-1-1, namely, a general nonlinear method and methods based on nominal stiffness and nominal curvature. The mentioned experiments also served, on the one hand, as a basis for the deterministic nonlinear modeling of the columns and, subsequently, for the probabilistic evaluation of the variability of the structural response. Finally, the results may be utilized as thresholds for the loading of the structural elements produced. The paper aims at presenting a probabilistic design that is less conservative than the classic partial safety factor-based design and alternative ECOV method.