ABSTRACT
Abstract The January 1994 Northridge, California earthquake provided an unusually severe test for buildings [1 ]. Although the earthquake was of relatively short duration, hundreds of steel buildings and several reinforced concrete buildings exhibited unexpected performance. Fortunately, no fatalities were attributed to damage associated with the unanticipated damage to concrete and steel buildings. This report describes damage to gravity load frame systems in reinforced concrete buildings where the seismic load resistance was provided by a Special Moment Resisting Frame (SMRF). Based on observed damage, changes were made to Section 21.7 of the American Concrete Institute Building Code ACI (318-95) [2]. Experimental work that indicates how these changes may affect performance of structures is presented in this report. Keywords: ACI 318-95, earthquake damage, gravity load frames.
