Structural Performance of Single and Double-Section CBF Braces with Different Lengths Under Cyclic Loading

Abstract

Concentrically Braced Frames (CBFs) are structural systems that are recommended to be constructed in earthquake-hazard areas. The brace is a CBF component that plays a role as an energy dissipator due to the seismic action. To result in a good performance, the brace is required to be strengthened. Adding a sectional area to the brace is one method for strengthening. Accordingly, the axial load is able to be distributed over a larger area, which may reduce the axial stress in the brace. So far, many kinds of research have been conducted to study brace behavior. However, the influence of adding a sectional area and increasing brace length to enhance brace performance has not yet been clarified. This paper experimentally investigated several braces under cyclic loading. Those braces were distinguished by their sectional area and length. The cyclic loading was managed by yield displacement control. The observation was mainly conducted on the performance parameter, which comprises strength, stiffness, and dissipation energy. The study discovered that enlarging the area section significantly increases the structural performance. Contrarily, the brace's performance tends to decrease when the brace is lengthened. Eventually, it can be recommended that enlarging the sectional area be taken as a solution to improve long-brace seismic performance in the CBFs system.