Strength and ductility of compact-flange I-girders in negative bending

This paper reviews available experimental and finite element test data pertaining to the negative moment-plastic rotation behavior of continuous-span steel I-girders with compact or ultra-compact flanges. Current American specification formulas for the pier-section strength of these types of members and a moment-plastic rotation model recently developed by the authors are examined against the experimental and finite element test results. Several weaknesses in current specification provisions are observed. The new M-theta(p) model avoids these weaknesses and provides a lower-bound approximation of the complete moment-plastic rotation response at the pier section. (C) 1998 Elsevier Science Ltd. All rights reserved.