Unequal width connections of square hollow sections in Vierendeel trusses

This paper presents the results attained in an extensive research programme on Vierendeel joints in hollow structural sections (HSS). A total of 29 specimens comprised of five distinct connection types were tested and their strength and stiffness properties were recorded.As most of the joints tested behaved in a semi-rigid manner, a stiffness method for analysing Vierendeel trusses comprised of such joints is presented. Design curves for prediction of joint strength are proposed and design examples of Vierendeel trusses under panel point loading are analysed.Two joint types are recommended. These are the haunch type of connection and the chord flange stiffener, both of which have adequate strength and stiffness characteristics.