Reliability Analysis of Steel Column Base Plates

Reliability analysis of steel column base pl ates designed i n a ccordance with B S5950 was 1 carried using Fir st Order Reliability Method (FORM). D esign vari ables s uch as desi gn axi al load and moment, concrete s trength, yield s trength of steel, cross-sectional dimensions of the plate a nd un iversal column, as well as thickness of the base plate were considered r andom a nd s tochastic. It was shown among other findings that, at a constant column axial load, as magnitude of applied bending moment increased on a section, the safety indices increased. It is interesting to note that, when the applied moment in th is c ase was d oubled, t he safety indices inc reased by a bout 3 .3 times (a t l ower c oncrete strengths) to about 1.3 times ( at higher concrete s trengths). Also, consistent relationship was shown to exi st between the design variables a nd the safety indices.