Confinement effect in reinforced concrete columns and finite element analyses

As the situation of our country in earthquake region it is necessary to build strength structuresagainst seismic forces. The pourness of the code prepared in 1974 caused the take effect of thenew code in 1998. The fast improvement of the performance based design in 1990?s and theenterance of the structural analyses programmes to the code of earthquakes caused a need fora new code, which has been prepared in 2005 as preliminary.It is seen that the concrete model of Mander et al. has entered the new Turkish earthquakecode. The models of concrete in the chronology in order; Hognestad concrete model (1951),Kent and Park concrete model (1971), Sheikh and Uzumeri concrete model (1982), ModifiedKent and Park concrete model (1982), Saatçioğlu and Ravzi concrete model (1992), Manderet al., (1988) concrete model.The confinement pressure is only calculated in the concrete models of Saatçioğlu and Razvi(1992), Mander et al. (1988) between the models which has been mentioned before.In this study, the effect of the reinforcement columns to confinement pressure are in order;concrete strength, diameter of longitudinal reinforcement, the yield strength of longitudinalreinforcement, diameter of lateral reinforcement, space between lateral reinforcement, theyield strength of lateral reinforcement and variation of the configuration of longitudinalreinforcement examined.In this study, the confinement pressure of columns in the articles of Heon-Soo Chung et all.(2002) and Claeson had been calculated with the comparison of Mander concrete model(1988) and Lusas software finite element analyses program.It is shown that at the end of the result of the finite element analyses varied for each column.On the other hand, the value of the confinement pressure doesn?t depend on the compressivestrength in the Mander et al. (1988) concrete model.The reinforcement square columns tested with concentric loading to get LVDT readings at thestructural laboratory of Yıldız Technical University as comparing with the experimental dataand 3D finite element analyses of this columns.Keywords: Reinforced concrete columns, concrete model, confinement pressure, finiteelement analyses.xviii