Abstract
First, experimental studies of concrete prisms with hoops subjected to axial force only are presented to clarify the three dimensionl behavior of colums, such as the confining effect by the hoops. This behavior is caused by the dilatancy of concrete in plastic region. Next, their simulation analysis is presented. It was executed by three dimentional non-linear Finite Element Method, wherein a reinforced concrete column was considered as being composed of core concrete, cover concrete, reinforcing steel and the bond between concrete and steel. In core concrete, the improvement of strength and ductility were represented by assuming three dimensional plasticity theory. The prisms were analysed in order to establish the non-linear parameter of concrete in the yield function, which was assumed in the constitutive equation. Here the vertical strain of concrete and strain of hoops were compared with the observed values. As the result, good agreement was obtained when an adequate non-linear parameter was adopted. This analysis is the simplest application model for a reinforced concrete column, which can be said to represent the compressive side of a column subjected to earthquake loads.
