Influence of joint eccentricity and rigidity on the load capacity of a space truss sub-assemblage

Abstract

Abstract Experimental testing of bolted and welded space truss sub-assemblages with large joint eccentricities has displayed satisfactory performance. Tests have been carried out on five sub-assemblages from a double layer (plate-like) space truss configuration. The distinctive features of the configuration employed were chord member continuity and the resulting large joint eccentricities. The particular layout adopted furnished orthotropic behaviour for stiffness and strength, so two sub-assemblage configurations were adopted. To provide control and comparisons a welded concentrically jointed sub-assemblage was tested in addition to the bolted and welded sub-assemblages. Although the large joint eccentricities reduced sub-assemblages stiffness and peak load capacity, the continuity of chords largely offset these reductions even when bolted joint details were used; for the welded joint cases peak load capacities were at least 50 per cent higher again. The stiffness of such systems is seen to be sensitive to member and joint imperfections, and joint slip.