Experimental and numerical investigation of lead-rubber dampers in chevron concentrically braced frames

This paper presents a theoretical and experimental evaluation of the application of lead rubber dampers (LRD) in the chevron bracing of structures. This device consists of a circular lead core with several layers of steel and rubber plates that are sandwiched together. This damper was manufactured at the earthquake engineering laboratory of Urmia University and installed inside a SDOF steel frame. The frame was placed on a shaking table, and its responses under several earthquake excitations were recorded. A 3D finite element model was created for the device, and hyper-elastic properties were determined for the rubber layers. To check the effectiveness of the device in mitigating the responses of multi-story frames, several nonlinear time history analyses were conducted on the structures using three earthquake excitations. The results indicate that significant reductions in the stories' drift can be achieved by installing lead-rubber dampers in the chevron bracing.