Theoretical Analysis of the Structural Performance of Space Trusses Commonly Used in Brazil

Abstract

Space trusses built in Brazil use basically two connection systems. In system 1, the node is formed by the superimposition of tubular section bars with stamped ends connected by a single bolt. The system 2 is a node consisting of welded steel plates to which bars with stamped ends or bars with end plates are connected. The authors have been engaged in theoretical and experimental studies to characterize the behaviour of these systems, including modifications to improve structural performance and establishing analytical models consistent with experimental behaviour. The theoretical analyses by finite element method have been performed utilizing the ANSYS and LUSAS software programs, using three distinct approaches: (i) analyses of isolated bars with section variations at the ends, (ii) analyses of the global behaviour of the structure considering the eccentricities on the connection, section variations in the bars and nonlinear behaviour, and (iii) numerical analyses of the local behaviour of the connection and its influence on global response and collapse modes.