Double Round Tube-Form Yielding Damper with Similar Behaviors in Tension and Compression for CBFs Buildings' Structures

Abstract

To enhance energy dissipation and prevent buckling in concentrically braced frames (CBFs), steel yielding dampers have been suggested, however, most of them have drawbacks, including differing tension-compression behaviors, complexity, and a lack of a straightforward design method. This paper introduces the double round tube-form yielding parts (DRTYP) steel damper, which exhibits consistent tension-compression behavior, easy manufacturing, and a simple design based on two relationships. The damper dissipates energy through two circular tube parts-one in tension, the other simultaneously in compression. The paper illustrates the damper's hysteretic behavior through lab tests and finite element analyses (FEA). Based on FEA results for DRTYP dampers with various tube dimensions, two relationships, linking initial stiffness and yielding strength to geometric features are provided. Also, a straightforward procedure for damper design in multistory buildings with chevron bracing is suggested. To demonstrate the damper's efficiency in reducing seismic responses, its application in a five-story building is discussed through nonlinear time history analyses. Results show that using appropriately designed DRTYP dampers can reduce the building's maximum roof acceleration and maximum base shear, on average, approximately 30% and 20%, respectively, compared to conventional CBFs.