Recent research advances of high strength steel structures and codification of design specification in China

High strength steel (HSS) with the nominal yield strength f (y)a parts per thousand yen460 MPa has been applied in numerous modern building and bridge structures all over the world. Steel structures using high strength steel have obvious advantages in structural, architectural, economical, environment protection and energy saving aspects. After a brief introduction of early studies, recent research advances of high strength steel structures in Tsinghua University in China are comprehensively reviewed. Systematic investigations have been carried out on static- and cyclic-loading behavior of high strength steels and their welded connections, residual stress of high strength steel hot-rolled and welded sections, overall and local buckling behavior of high strength steel columns under axial compression, seismic behavior of high strength steel columns under combined bending and compression, bearing and slip resistance of bolted connections with high strength steel slices. The research results show that mechanical behavior of high strength steel structures has been improved much compared with ordinary strength steel structures, so the design methods in current design codes or specifications need be updated to be applicable to high strength steel structures. Therefore, as the chief-editor institute, Tsinghua University has organized 34 institutes including universities, design and research institutes, steel structure fabricators, and steel manufacturers, to codify a new code, i.e. Design Specification of High Strength Steel Structures in China. Based on the above research results, new design methods and calculation formulae applicable to high strength steel structures are incorporated into this design specification. The outline of this specification is discussed in detail in this paper.