NCEER-93-0006 | 4/5/1993 | 110 pages
TOC: The table of contents is provided.
Keywords: Bracing Systems, Reinforced Concrete Structures, Inelastic Response, Mathematical Models, Experimental Evaluation, Energy Dissipation, Scale Models, Dynamic Response Analysis, Damage Mechanisms, Viscoelastic Dampers, Shaking Table Tests, Input Energy, Stiffness, Damping Devices, and System Identification.
Abstract: The addition of viscoelastic braces in structures for vibration reduction was proposed and implemented in the past decade in metal models or full-scale structures. Viscoelastic braces provide energy dissipation, while the structures remain by-and-large elastic. In reinforced concrete structures, the seismic response is by-and-large inelastic, which is often accompanied by permanent deformations and damage. The addition of viscoelastic dampers can dissipate energy at the early stages of cracking of the concrete elements and reduce the development of damage. However the addition of viscoelastic dampers may stiffen the structure unnecessarily producing increased inertial forces and base shears when subjected to seismic motion. The quantification of the influence of viscous and elastic stiffness properties of dampers during the inelastic response of reinforced concrete structures is thus the subject of this investigation. Models for analysis of inelastic response with damage indexing for reinforced concrete structures that include viscoelastic braces are developed and calibrated using experimental data produced by shaking table tests. These models are then used to determine the variation of expected damage in the presence of damping and quantify the hysteretic energy dissipation along with the damping energy.