STUDIES ON RESPONSE CONTROL OF A FRAME STRUCTURE SUBJECTED TO EARTHQUAKE LOADING USING ELASTO-PLASTIC ENERGY ABSORBERS

摘要

Elasto-plastic passive energy absorbers of yielding type are often used as supplemental damping devices in structures for controlling the large seismic response under earthquake loading. These devices function based on the large and stable energy dissipation obtained using the inherent ductile property of metallic substances by inducing large plastic deformation in them. The X shaped or hourglass shaped metallic device made of steel is a classic example of elasto-plastic yielding type characterised by large and stable hysteresis loops under cyclic loading. This paper presents a shake table experimental study conducted on a three storey steel frame model incorporated with supplemental damping devices of metallic yielding type having X shape for the increased energy dissipation ability to reduce seismic response under earthquake loading. These devices were incorporated within the frame between adjacent floors in the form of chevron braces so that they are more efficient in the loading direction. The increase in the energy dissipation ability of the frame under seismic loading was demonstrated from the experimentally obtained force-displacement hysteresis loops computed using the measured inter-story drifts and floor accelerations.