Performance study of eccentrically braced steel frames with core tube flange connection

Abstract

This paper proposes a kind of assembly brace connections adapted to the core tube flanged column connection joint of the frame-brace structure, starting from the eccentrically braced frame structure in the steel frame system and designing and completing a set of proposed static tests of the eccentrically braced frame with the core tube flanged column connection joint. By conducting in-depth analysis and research at three levels, namely the seismic performance of the eccentrically braced frame system, the performance characteristics of the core tube type flanged column connection joints, and the performance of assembled brace connections, the study has yielded insights into the force mechanism and failure modes of the core tube type flanged column connection joints within the eccentrically braced frame system; the eccentrically braced frame system has been validated to possess good seismic performance by analyzing hysteresis curves, typical section strains, and bolt forces. These analyses have shown that the system can meet the seismic requirements. Moreover, the assembled brace joints were destroyed later than the braces, indicating that the assembled brace connection joints could fulfill the requirement of “strong joints.”