Experimental study on seismic performance of glued laminated timber K-braces frame structures
Wu Yi1 Yang Chun2,3 Chen Libang1 Wu Juntao1
1. Guangzhou University, Guangzhou 510006, China;
2. School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China;
3. State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, China
Abstract：To achieve a combination of rigidity and ductility in a glulam high-rise structure, a stiffness unit and a damping unit are constructed, respectively. The stiffness unit is a glulam frame with glulam brace reinforced by carbon fiber, and the damping unit is a glulam frame unit with a metal damper added to the stiffness unit. In this work, reversed cyclic loading tests were carried out on a single-floor single-span stiffness unit and damping unit. After the failure of the metal damper in the damping unit, the tested damping unit was renovated by welding steel plates, and the same reversed cyclic loading tests were implemented. Seismic performance, failure patterns, hysteretic curve, skeleton curve, ductility, strength degradation, stiffness degradation, and energy dissipation capacity of the glulam frame specimen were investigated. Results show that instability and splitting failure can be avoided in the carbon fiber-reinforced glulam braces, the damping unit exhibits more stable hysteretic characteristics, and the ductility coefficient is 2.68%～19.2% higher than that of the stiffness unit. Thus, in damping unit, destruction of components can be significantly improved, and glulam braces and beam-column frame are protected effectively. After the failure of the damper, the renovated damper unit specimen still possesses the stiffness and bearing capacity equivalent to those of the stiffness unit, indicating that after the failure of the damper taken as the first line of defense, the glulam frame still has a certain seismic performance, forming a dual seismic defense line system with the damper as the first defense and the braced-frame as the second line of defense.
