Double Chord RHS Trusses: Analytical Model

An analytical method is proposed and a computer program developed to analyze double chord trusses comprised of rectangular hollow sections. Three types of local yield mechanisms are incorporated: 1 Plastic hinge formation; 2 member yielding due to plastic load limit; and 3 yielding of shear springs that model the connections. The analysis is carried out in an incremental manner. Overall failure of a truss is declared when either an overall mechanism forms or excessive deflection occurs. A bilinear axial forcemoment interaction diagram is used to allow for reduction in the plastic moment capacity due to the presence of axial force. Results from analyses of Warren trusses with three different types of connections are presented and compared with those obtained experimentally from a previous study. Overall, very good agreement is observed thus verifying the validity of the analytical model.