Experimental and Analytical Studies of Base Isolation Systems for Seismic Protection of Power Transformers

Keywords: Experimental studies.  Analytical studies.  Base isolation systems.  Seismic protection.  Power transformers.  Tri-axial earthquake simulator testing.  Seismic isolation.  Base displacement.  Sliding bearings.  Lead rubber bearings (LRB).  Segmented high-damping rubber bearings.  Seismic responses.  Numerical simulations.  Force-displacement hysteresis.  Friction.  Vertical motion.  Bushing connecting cables.

Abstract: This report presents a comprehensive study involving tri-axial earthquake simulator testing on seismic isolation of electric power transformers.  In this study, two isolation systems were developed, one using sliding bearings combined with rubber bearings and the other segmented high-damping rubber bearings.  Tri-axial earthquake simulator testing was performed using a large-scale transformer model equipped with real bushings.  Important observations were made on the seismic responses of the transformer and its bushing.  In conclusion, the base isolation technology, when properly designed, is a highly effective measure for seismic protection of power transformers.  References, figures and images are incorporated.