An experimental study and calculation on the fire resistance of concrete-filled SHS and RHS columns

The behavior of concrete-filled steel square hollow section (SHS) and rectangular hollow section (RHS) columns with or without fire protection subjected to axial or eccentric loads has been experimentally investigated and the results are presented in this paper. The parametric and experimental studies provide information for the development of formulas for the calculation of the fire resistance and the fire protection thickness of the composite columns. The main objectives of this paper were threefold: first, to report a series of fire tests on composite columns with square and rectangular sections. Secondly, to analyze the influence of several parameters, such as fire duration time, sectional dimension, slenderness ratio, load eccentricity ratio, strength of steel and concrete on the residual strength. index (RSI) of the composite columns. Finally, to develop formulas for the calculation of the fire resistance and the fire protection thickness of the concrete-filled steel SHS and RHS columns, such formulas to be suitable for incorporation into building codes. The concepts of this paper were used to provide data on the necessary fire protection measures for the concrete-filled steel SHS columns used in a high-rise building, Ruifeng, Shangye Building in Hangzhou City, in southern China. (C) 2002 Elsevier Science Ltd. All rights reserved.