The capacity of grade C450 cold-formed rectangular hollow section T and X connections: An experimental investigation

The paper presents the results of an experimental program which consists of 15 T and X truss joints fabricated from grade C450 cold-formed rectangular hollow sections (RHS). The aim is to study the effect of the increased yield stress and the somewhat reduced ductility resulting from the cold-working process on the static capacity of these joints. The experimental program was designed to include the full range of possible failure modes and covers a comprehensive spectrum of geometries, including commercially available sections which fall outside the CIDECT limits in terms of wall slenderness ratios. In a next step, the results are compared to the current CIDECT design rules where applicable. In particular, the need for a reduction factor of 0.9 on the capacity of grade C450 connections, imposed by both the CIDECT rules and the Eurocode, is evaluated.