Tubular space trusses with simple and reinforced end-flattened nodes-an overview and experiments

The use of tubular space frames made of continuous chord members has substantially increased over the last few years. This growth is mainly due to lower fabrication costs and high erection speed associated with these structural systems. The chord members are usually made of cold-formed shapes or tubes. The connection between the chords and diagonal members is commonly made by staking end-flattened diagonal members over the chords linked by a single large diameter bolt. In spite of this fact, the actual structural behaviour of these connections is still not fully understood. This paper describes six full-scale tests performed on spatial structures to investigate their structural response. Based on these experiments, the structural behaviour, up to collapse, of simple eccentric and reinforced eccentric nodes was discussed. A study of structural reinforcements, created to improve the structural load carrying capacity and minimise deflections, is also one of the main foci of the present paper.