Plastic Deformation of Column Base in Steel Moment Frames Subjected to Strong Earthuuakes

Abstract

This paper is concerned with the demand for ductility of column base in steel moment frames. Numerical response analysis was carried out for 15 frames against a variety of ground motions. In this paper, the magnitude of plastic deforma tion introduced into column base is described. Maximum plastic rotation, maximum increment of plastic rotation during a half cycle of vibration, and the range of variable plastic rotation are considered as the parameters that represent the magnitude of plastic deformation. The results are summarized as formulas to predict those param eters based on maximum story drift angles.