STUDY ON SINGLE ANGLE BRACE JOINT WITH LOAD-CARRYING CAPACITY IN SEISMIC REINFORCEMENT

Abstract

In this study, we propose a new consideration of seismic reinforcement using a single angle brace joint. The load-carrying capacity of such joints was investigated by applying tension stress to them until an angle member section became fully plastic. In this case, the earthquake input energy was used enough for the plasticity of the angle members. However, this structural design has one limitation: if the joints do not have sufficient load-carrying capacity, they will break before yielding. This decreases the ductility of the structural frame. Therefore, structural designers have to ensure that a single angle brace joint has sufficient load-carrying capacity. However, the stress transmission characteristics of an angle brace joint have not yet been clarified sufficiently. In seismic retrofit based on design guidelines, the index of ductility is determined based on a two-level evaluation of the joint strength. The authors have confirmed the reliability and validity of this method from the results of online seismic response tests and considerations concerned with the material yield ratio.