Mohammad Arabpanahan - School of Civil Engineering, College of Engineering, University of Tehran
Mohammad S. Marefat
Mohammad Khanmohammadi

There are many concrete structures that have been constructed before 1970, and have been reinforced by plain bars. For retrofitting these structures, it is necessary to investigate seismic performance of them, and to evaluate their ductility, strength and stiffness. The objective of this paper is to propose a numerical model to simulate the response of concrete columns with old design details. The model is based on bond-slip properties of plain bars derived from pullout tests. The global behaviour, then, is calibrated by results of monotonic tests performed on three concrete columns reinforced by plain bars. The numerical modelling carried out by MATLAB programming. For modelling, three displacement components of column, under lateral loading have been considered; bending, slip, and shear. By means of the model, important seismic characteristics of the columns (ductility, strength and stiffness) can be estimated and compared with allowable limits in current design codes

Reinforced concrete, Plain (smooth) bar, Seismic assessment