Effects of reinforcement slip on hysteretic behavior of reinforced concrete frame members

A new approach in describing the nonlinear hysteretic behavior of reinforced concrete (RC) frame elements is proposed. This approach consists of isolating the basic mechanisms that control the hysteretic behavior of girders and columns into individual subelements that are connected in a series to form the complete girder or column element. This paper discusses in detail the subelement that represents the effect of reinforcement slip in the critical region and in the anchorage zone adjacent to the beam or column. Thus, it can represent the fixed-end rotations that arise at the beam-column interface caused by bond deterioration and reinforcing bar slip in the beam-column connection region of RC frames. The proposed model is validated by correlation studies with experimental measurements of the load-displacement response of beam-column subassemblies under static load reversals. The analytical results show agreement with experimental data.