SEISMIC BEHAVIOR OF MOMENT-RESISTING STEEL FRAMES - EXPERIMENTAL-STUDY

An experimental evaluation of the seismic performance of moment-resist ing steel frames using weak-column strong-beam joints is described. Th is study is a continuation of an analytical investigation described in a companion paper. Five half-scale specimens are tested using an inel astic substructure technique of the pseudodynamic test method. Most of the structural frame is analyzed using standard inelastic techniques while a critical component of the frame is tested. Results from this s tudy suggest that weak-column strong-beam frames have sufficient ducti lity to sustain the inelastic demand induced by a major seismic event, but only if the base shear strength is larger than the minimum requir ed by the Uniform Building Code. A frame tested with the minimum desig n base shear strength failed during the earthquake. Other characterist ics, such as slenderness of the column cross section and axial load ra tio, affect hysteretic behavior, but the overstrength of base shear ca pacity has the largest influence on the satisfactory performance of we ak-column strong-beam frames.