Numerical investigation of the behaviour of high strength steel extended end-plate counnections

ABSTRACT: Using high strength steel has some advantage like reducing weight of the structures. That means less consumption of steel. The smaller member sizes are more favoured by architects. High strength steel represents limited deformability. In this study the deformation of the connection is mainly caused by the deformation of the end-plate and elongation of the bolts. A series of finite element investigation was conducted to study the high strength steel extended end-plate moment connections subjected to monotonic loading. The finite element model of connection is calibrated by using experimental test results of extended end-plate connections. The steel grade of plate and bolts and the thickness of the plate were changed to investigate the behaviour of the connection. The finite element analysis results demonstrate that the high strength steel extended end-plate moment connections can be suitable for use in steel moment frame structures. The results indicate that by decreasing the end-plate steel grade the ductility was increased but the moment resistance was decreased. 12.9 grade bolts have less ductility than 10.9 grade bolts and 8.8 grade bolts have more ductility than both 12.9 and 10.9 grade bolts. The thinner end plate showed more ductility and lower moment resistance than the thicker end plate. The results obtained from the finite element modeling indicated that the finite element method is a good choice for estimating the behaviour of endplate connections. Keywords: High Strength Steel, Extended End-Plate Connections, Finite Element Method, Moment Resistance, Ductility. …………………………………………………………………………………………………………………………