Studies on the behavior of Reinforced Concrete Short Column subjected to fire

•500°C isotherm method used to assess the capacity of columns subjected to fire.•The various parameters that influence the fire rating of columns are evaluated.•Fire rating based on different failure criteria and design fire rating determined.•Interaction curves plotted to predict failure of columns in fire and uniaxial moment. The paper investigates the axial capacity of reinforced columns exposed to fire. The simplified method namely 500°C isotherm method explained in Eurocode 2 is used to assess the capacity of the column. Finite element software ANSYS is used to perform the thermal analysis. A set of numerical studies were carried out to quantify the effect of various parameters on short columns subjected to fire. The study is performed on columns of different cross-sections to investigate the effect of eight parameters, namely the thermal boundary conditions, grades of concrete, grades of steel, types of aggregate, distribution of reinforcement on column faces, concrete cover, load eccentricity and support conditions. The fire ratings based on various failure criteria are determined, and minimum rating is accepted as design fire rating. A simplified interaction curve to predict the failure of columns under fire subjected to axial load and uniaxial moment for square cross-sections was also developed.