Fire Resistance of Circular Steel Columns Filled with Bar‐Reinforced Concrete

Experimental and theoretical studies have been performed to predict the fire resistance of circular hollow steel columns filled with bar‐reinforced concrete. A mathematical model to calculate the temperatures, deformations, and fire resistance of the columns is presented. Calculated results are compared with those measured. The results indicate that the model is capable of predicting the fire resistance of circular hollow steel columns, filled with bar‐reinforced concrete, with an accuracy that is adequate for practical purposes. The model enables the expansion of data on the fire resistance of circular concrete‐filled steel columns, which at present consists predominantly of data for columns filled with plain concrete, with that for columns filled with bar‐reinforced concrete. Using the model, the fire resistance of circular concrete‐filled steel columns can be evaluated for any value of the significant parameters, such as load, column‐section dimensions, column length, and percentage of reinforcing steel without the necessity of testing.