Behavior of Sway Two-Bay, Two-Story Composite Steel Frames in Fire

Abstract

The experimental results of three full-scale two-story, two-bay, composite steel frames under furnace loading are described briefly. During tests, the composite beams and steel columns were exposed to fire, and only the beam-to-column connections of the tested frames were protected. The furnace temperature, composite steel beam temperature, steel column temperature, horizontal displacements of the columns, and vertical deflections of the composite beams as well as the complete deformation process of the test frames observed during the heating phase and the cooling phase are given. By introducing the slope-deflection equations and joint equilibrium conditions at each joint, the critical temperatures of the buckling of two-story, two-bay, composite steel frames are determined for different furnace scenarios; therefore, this method can consider the effect of the axial force at different levels. The calculated critical temperatures agree well with the experimental results.