SENSITIVITY ANALYSIS ABOUT INFLUENCE OF OUT-OF-PLANE DEFLECTIVE DEFORMATION UPON COMPRESSIVE STRENGTH OF STEEL PLATES

In this study, it is aimed at verifying the relationship between amount of the initial deflective deformation of simply supported steel plates and ultimate compressive strength of them through elasto-plastic finite deformation analysis. When initial deflection has been controlled smaller unitl now or out-of plane deformation has become large after an earthquake, the current compressive strength curve of steel plates in Japan cannot be applied. Therefore, more accurate prediction method have been required in near future, on behalf of rational design of steel structures. In other words, it is needed to make clear the relationship between the initial imperfection and the strength of simply supported steel plate. For this purpose, the parametric study on compressive strength of steel plates taking the initial deflection and a width-thickness ratio parameter into account was carried out. At first, a limit width-thickness ratio parameter corresponding to maximum width-thickness ratio parameter where compressive strength of a steel plate reaches yield stress of steel material, was proposed through the parametric study. And, predicted equation for calculating a limit width-thickness ratio parameter was developed. Secondary, the relationship between the ultimate compressive strength of a steel plate and amount of initial deflection was clarified. In addition, estimated equations based on results of various numerical analysis were developed. Finally, the prospect of this future study was discussed.