EXPERIMENTAL STUDY ON SEISMIC RETROFITTING STEEL BRACE OF EXISTING RC SCHOOL BUILDINGS WITH LOW-STRENGTH CONCRETE

Abstract

Seismic retrofitting with steel brace is multiuse to the earthquake-resistance strengthening work in existing RC buildings. This seismic retrofit method is most often used when a building structure has insufficient strength and it is not possible to upgrade its ductility. The indirect connection with existing columns or beams and steel brace must be effective for shear, if the strength of the indirect connection are not adequate and if the details are not properly designed, the structure as a whole is not likely to display effective seismic performance. However, there has been no study that tried to apply this seismic retrofit method to existing RC buildings with very low-strength concrete. In this research, we confirmed the effect of increase the resistance of the structure to seismic forces by seismic retrofitting with steel brace through two series of tests. As a test results for the RC frame and the indirect connection with low-strength concrete, it has been understood for the earthquake performance to improve by the earthquake strengthening, and to satisfy the required performance.