Development of SMART Base Isolation Using Linear Motion Guide

Abstract

This study addresses the design of nonlinear oil-spring damper that render an effective re-centering mechanism for a linear motion (LM) guide base isolation system. A nonlinear stiffening behavior of the damper offers added advantage of re-centering mechanism. The proposed LM guide with damper system works in a similar fashion as that of the LRB isolation system supplemented with re-centering mechanism for small to high level of shaking. For high intensity shaking, the proposed system minimizes the peak horizontal displacement in addition to keeping the residual displacement close to zero. To demonstrate the concept of the proposed base isolation system, a numerical study is conducted with a steel moment-resisting frame when subjected to ground motions of varying hazard levels. It has been found from this study that the proposed LM guide base isolation system is effective in limiting the peak bearing displacement and making the residual bearing displacement negligible for varying hazard levels.