Five‐Spring Element for Biaxially Bent R/C Columns

Abstract

The cyclic behavior of reinforced concrete columns subjected to biaxial bending was determined using a hysteretic element consisting of five axial springs. Four composite springs and one concrete spring are used. Their basic properties are controlled by the calculated balanced moment and axial force. A new simple hysteresis model was used for the composite springs and an existing model was used for the concrete spring. The five‐spring element (FSE) was evaluated based on its performance in simulating the response of several reinforced concrete test specimens. The element appeared to be successful in reproducing the response as long as the peak axial force did not exceed the balanced axial force. The FSE was also used to determine the response histories for several bridges. The results indicate that the response histories found based on FSE can be considerably different from those based on an elastoplastic yield surface model.