Polymer Matrix Composite Panels for Seismic Energy Dissipation

This paper addresses the analysis and experimental investigation of plymer matrix composite (PMC) panels utilized for seismic energy dissipation. The concepts rely on introducing considerable shear deformation at strategically located layers. The layers at which the shear deformation to take place, referred to here as the interface layers, are composed of a combination of solid viscoelastic material combined with honeycomb material. As part of this research, a series of experiments were performed to quantify the energy dissipation characteristics of the interface layer. The effects of thickness, loading rate, and the ratio of the volume fractions of the constituent materials are investigated. Utilizing the results obtained from material testing, three conceptual panel designs were tested to assess the over all energy dissipation in a structural system. Results obtained from the experimental program were used to further verify finite element models that were used to simulate the response of several structural systems retrofitted with the seismic energy dissipating panel concepts. A theree-dimensional (3D) nonlinear finite element analysis was carried out to evaluate the damping effective of added PMC panel with viscoelastic interface layers in the retrofitting of the Multidisciplinary Center for Earthquake Engineering Research (MCEER) demonstration hospital structure. An equivalent Kelvin model consisting of an elastic spring and a linear viscous damper combined in parallel is proposed for the PMC panel with viscoelastic interface layer. The retrofitted structure was subjected to MCEER west coast ground motions. Significant increase in the system damping was obtained with the added PMC panel. Both the modal strain energy method and logarithmic decrement method showed the PMC panel contributed 8% damping to the hospital structure. Time history analysis results showed the peak displacement and acceleration responses were reduced a lot and vibration damped out very quickly.