ABSTRACT
This chapter provides a comparison between theoretical values of axial forces calculated by the modified method. As the axially loaded pin ended column starts to lose its stability and deforms laterally, a shortening in the vertical height of the column takes place. The chapter describes a modified method for determining the value of axial forces generated in axially restrained pin ended steel columns subjected to elevated temperatures by taking into account the column vertical shortening due to buckling. A comparison between theoretical values calculated by the current and the modified methods was performed for various restraint degrees. The comparison shows that the modified method gives satisfactory agreement with test data. The performance of steel columns under high temperatures has a significant effect on the fire safety of steel buildings. The exposure to elevated temperatures deteriorates the mechanical properties of the steel including its Young modulus and plastic deformations may develop.
