Testing of Passive Energy Dissipation Systems

Abstract

Over the period 1986 to 1991, seven different passive energy dissipation systems were studied in experimental research programs at the Earthquake Engineering Research Center of the University of California at Berkeley. This paper presents an overview of these studies, describing the different types of devices, the results of the shake table experiments, and associated analytical work. Four of the systems studied are friction systems, and of these, three (Sumitomo, Pall, and Friction-Slip) are based on Coulomb friction. The fourth is the Fluor-Daniel Energy Dissipating Restraint, which is a device capable of providing self-centering friction resistance that is proportional to displacement. The three other systems all have different energy dissipation mechanisms: ADAS elements, which utilize the yielding of mild-steel X-plates; viscoelastic shear dampers using a 3M acrylic copolymer as the dissipative element; and Nickel-Titanium alloy shape-memory devices that take advantage of reversible, stress-induced phase changes in the alloy to dissipate energy. The effectiveness of the various systems is evaluated by comparing the response of the test structures without and with the energy dissipators. In some cases, where devices were studied using the same test structure, they are compared directly. All of the systems investigated exhibited characteristics beneficial to improved structural response to earthquake loading.