Development of Finite Element Model for a Special Lead Extrusion Damper

A significant amount of seismic energy is imparted to the structures during earthquakes. The energy spreads within the structure and transforms in various energy forms as dissipated through the structure. The conventional seismic design provides specific ductile regions, namely plastic hinges, on structural elements. Therefore, the energy dissipation capacities of the structural elements and the structure enhance. However, this approach accepts that the deformations will concentrate on the plastic hinge zones and severe damage may occur on structural elements within deformation limits that are defined by the seismic codes. The modern seismic design aims to dissipate a large portion of the seismic input energy by installing energy dissipating devices (EDDs) to the structure. Thus, deformation concentrates on EDDs which can be replaced after an earthquake, and energy demand for structural elements is decreased. Lead extrusion damper (LED) is a passive EDD that utilizes the hysteretic behavior of lead. In this paper, the preliminary results of the developed three-dimensional finite element model (FEM) for a LED is presented. The results obtained from the finite element analysis (FEA) were compared with the experimental ones in which LEDs were exposed to sinusoidal displacements. Also, the applicability of the developed FEM was checked for different component dimensions given in the literature. The comparison study yielded a satisfactory consistency. Additionally, the maximum relative difference obtained for the literature devices was reduced to 12% from 39% by the developed FEM.