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Proceedings of the International Conference on
Advances and New Challenges in Earthquake
Engineering Research, Hong Kong Volume
BEHAVIOR OF SEISMIC PROTECTIVE DEVICES: A
COMPUTATIONAL MECHANICS APPROACH
G. F Dargush, H. Cho and R Radhaknshnan
Department of Civil, Structural and Environmental Engineering
State University of New York at Buffalo
135 Ketter Hall, Buffalo, New York 14260, USA
ABSTRACT
Structural control technology continues to advance rapidly on many fronts through the introduction of
new devices and systems. At the same time, there is a need to continually improve our understanding
Of existing protective technologies via carefully controlled physical experiments and mathematical
modeling. In this paper, we present work related to computational continuum mechanics analysis of
several passive devices. In particular, we consider two different metallic dampers and a solid
viscoelastic damper. For each case, an overview of the constitutive modeling is provided, along with
some details from the finite element analyses relating to damper behavior. Finally, we argue that such
an approach is advisable in general, as we attempt to move toward the goal of developing disasterresilient
communities.
INTRODUCTION
A wide variety of seismic protective systems have been developed over the past several decades and,
as the concept becomes more well known, an increasing number of structures employing these systems
appear each year Whether one considers base isolation systems (Skinner et al., 1993), passive energy
dissipation systems (Soong and Dargush, 1997; Constantinou et al., 1998) or active/semi-active control
systems (Soong, 1990), there are key elements that will to a large extent determine the performance of
the entire structure during significant earthquakes In many cases, these key elements are the seismic
protective devices. In this paper, we advocate a philosophy that treats seismic protective devices as
critical components, necessitating a high level of reliability This, in turn, requires a rigorous program
of engineering analysis, testing and design. Here we focus on aspects associated with engineering
analysis, and present the application of computational continuum mechanics to study the behavior of
several passive devices.
First, we examine metallic dampers and develop a two-surface cyclic plasticity model to characterize
their behavior. Model parameters are established to capture essential features of structural steel under
constant amplitude cyclic loading The resulting model is then utilized in finite element analyses to
study the behavior of an E-damper for seismic isolation systems and a triangular plate energy absorber
(TPEA) for passive energy dissipation. In both cases, the numerical solutions are compared with the
results of physical experiments. Additionally, several significant aspects of the response can be
elucidated with a computational mechanics approach.