Investigation of Seismic Behavior of End Plate Moment Connections with Iron-Based Shape Memory Alloys

In the 1994 Northridge and 1995 Kobe earthquakes, a large number of conventional bending frames suffered brittle fractures at the beam-to-column joint. Researchers have found that structural components of structural systems are very effective in controlling the energy caused by dynamic loads, especially earthquake and explosion loads. In recent years, Iron-based shape memory alloys, which have two important properties of superelasticity and shape memory behavior, have been used to improve the seismic performance of structural systems. This study investigates the energy dissipation capability and other properties of moment connection with expanded end-plate and bolts made of super-elastic ferrous based memory alloys. The 3D connectivity models are built using ABAQUS finite element software. By applying cyclic loads to the end of the beam, its behavior has been studied. In this research, two types of four-bolt connections, one with the behavior of a thick plate and the other with the behavior of a thin plate, have been modeled, and in each case, the connection behavior with and without the use of shape memory materials has been evaluated and compared. The use of these materials in connection with thick plate behavior has increased the ductility of the connection by 35%, and the connection has compensated 93% of the deformation and returned to its original state. In connection with thin plate behavior, the increase in ductility of the connection is 54% and 85% of the endured deformation has returned to the initial state.