Tall buildings in wind and earthquake-prone regions require force-resisting steel plate shear wall systems with excellent mechanical properties. However, the boundary beams and columns of steel plate shear walls are susceptible to axial forces and bending moments which may cause the generation of plastic hinges and failure if not controlled. Additionally, local buckling of these systems induces noise and out-of-plane deformation that has remained a great challenge. Therefore, the development of effective ways of preventing local buckling is highly desirable.
The development of buckling-restrained steel plate shear wall systems comprising of connections to boundary beams and columns was a great step in preventing buckling effects in steel plates. It entails a two-sided reinforced-concrete (RC) panel used to improve the hysteretic behavior and ultimate shear resistance. Unlike the concrete shear walls, these systems can be configured as a core structure and can be constructed with less time and at a reduced wall thickness. Unfortunately, their seismic performance under earthquake excitations has not been fully explored even though the inner plates exhibit properties that favor good seismic performance. However, conventional buckling-restrained steel plate shear wall systems have large single reinforced-concrete panels that restrains its engineering applications.
To this note, Qihao Han, Yongshan Zhang, and Dr. Dayang Wang from Guangzhou University together with Dr. Hiroyasu Sakata from the Tokyo Institute of Technology proposed new buckling-restrained steel plate shear wall systems assembled with multi-reinforced-concrete panels. Finite element models of two test specimens with hinged frames were developed to investigate the general mechanical behavior of the system. Furthermore, numerical simulations based on monotonic and cyclic loadings were carried out to determine the effects of various parameters: steel plate slenderness ratio, the number of reinforced-concrete panels on one side of the inner steel plate and gap width between the reinforced-concrete panels. The work is currently published in Journal of Constructional Steel Research.
The mechanical behavior of the multi- reinforced-concrete panel system underwent four phases: initial elastic phase, shear yield phase, post-shear yield phase, and pre-failure phase. The system provided stable shear and superior energy dissipation capacity since the single reinforced-concrete panels were divided into multiple reinforced-concrete panels. During the bending moment, the boundary column of the new system required significantly less internal force as compared to the conventional buckling-restrained steel plate shear wall system. Additionally, the damage on the reinforced-concrete panels was greatly decreased. It was worth noting that the tension damage of reinforced-concrete panels was affected by the number of the panels and the gap width of the system.
It was necessary to perform numerical analysis and quasi-static cyclic tests to investigate the seismic behavior of the multi-RC system. A mutual agreement between the experimental and numerical results was observed. With a significantly reduced internal force, a maximum reduction of bending moment of 60% was attained. In addition to the superior mechanical properties, the construction of multi-RC systems is economically viable. The study will, therefore, lead to the development of advanced materials for the construction of tall buildings.
Han, Q., Zhang, Y., Wang, D., & Sakata, H. (2019). Seismic behavior of buckling-restrained steel plate shear wall with assembled multi-RC panels. Journal of Constructional Steel Research, 157, 397-413.Go To Journal of Constructional Steel Research