Study on Seismic Behavior of Different Forms of Eccentrically Braced Steel Frames

Abstract

The arrangement of eccentric bracing has a significant impact on the seismic performance of structures. However, there is no further stipulation on different forms of eccentric bracing in the current Chinese code. At the same time, there is a lack of research on the seismic loss of eccentrically braced structures by Chinese domestic scholars. Therefore, this paper designs different forms of eccentrically braced frames and analyzes them according to the concept of seismic engineering based on performance, which provides some reference for the selection of the eccentrically braced steel frame structure layout in future engineering practice. In this paper, K-shaped, V-shaped, and D-shaped eccentrically braced steel frame structures with 3, 5, and 8 floors are designed, and the finite element analysis model is used for static napping and dynamic time history analysis. The results show that the K-shaped eccentrically braced structure has the best performance in bearing capacity and stiffness and has good seismic and collapse resistance performance. In the FEMA P-58 seismic assessment and vulnerability assessment, it is found that the V-shaped eccentrically braced structure has the smallest loss. However, it is necessary to fully consider the acceleration sensitivity of the non-structural components in the design. In general, the seismic performance of the eccentrically braced structure is improved by the energy dissipation beam yielding to consume energy, which provides a useful reference for structural design.

Keywords

• eccentric braces
• vulnerability
• structural response
• seismic loss