Experimental and Analytical Investigation of Cyclic Behavior of an Innovative Multilevel Control Damper

Abstract

Multilevel dampers are a developed type of metallic yielding damper that belong to a category of passive energy dissipation devices. This study presents a proposed multilevel energy dissipation device for enhancing the seismic performance of structural systems. The damper utilizes a configuration comprising two steel-pipe segments supported by an angle section. A controlled frictional contact mechanism governs load transfer within the device. The performance of the proposed device is evaluated through a combined experimental and numerical investigation. The cyclic response of a physical prototype is experimentally characterized. Subsequently, a validated finite element model of the device is developed using ABAQUS software, demonstrating good agreement between experimental and numerical results. Additionally, the influence of steel pipe diameter on damper behavior is explored through numerical simulations of three models with varying diameters. Results from experimental testing and numerical analysis indicate that the equivalent viscous damping ratio of the prototype damper is 20.3%, while the numerical models exhibit a range of 19.8% to 25.2%. This multilevel behavior allows the proposed device to effectively control and dissipate seismic energy through staged responses, exhibiting appropriate stiffness, strength, and energy dissipation capacities at different demand levels.