Behavior of plate-to-circular hollow section joints of 600 MPa high-strength steel

While the recent high demand for high rise buildings has led to the development of high-performance and high-strength steels, the requirements for structural-performance steel for such buildings have been raised as engineers recognized the potential wreak damage that an earthquake could cause on a tall building. Many studies on high-strength steels have explored such requirements, but appropriate design equations are needed for the case of hollow structural section (HSS) due to the design equations that limit the maximum yield stress up to 360MPa in the design codes (AISC, 2011; KBC, 2009). This study investigated the behavior of 600MPa plate-to-circular hollow section joints subjected to applied moment and shear force by experiment and finite element analysis (FEA), and the results are compared with current design equations. The nominal strength of AISC (2005) (or KBC (2009)) overestimated the tested strength in the range between 105% and 137%. It is found that the nominal strength equation of AISC (2011) is reasonably revised in comparison to those of other design codes.