Out-of-plane elastic buckling behavior of hinged planar truss arch with lateral bracings

• Buckling load of planar truss arches with continuous bracings is obtained.
• Design approach of planar truss arches with discrete bracings is proposed.
• Out-of-plane buckling of chord tubes with two kinds of joints is discussed.

This paper is concerned with the out-of-plane elastic buckling behavior of planar truss arch with continuous or discrete lateral bracings. Firstly, planar truss arches with continuous lateral bracings are studied, and a closed form solution of out-of-plane elastic buckling load is obtained theoretically. As for planar truss arches laterally restrained with discrete bracings, two key parameters, namely lateral bracing threshold stiffness and out-of-plane elastic buckling load of an arch segment between two adjacent bracings, are investigated by the finite element method, respectively. Besides, it is found from finite element results that, if the planar truss arch is manufactured by using intersecting joints between web members and chord tubes and is laterally restrained on top chord tubes, the out-of-plane buckling of bottom chord tubes will fully be prohibited. However, the gusset-plate connections between chord tubes and web members cannot prevent the planar truss arch from the out-of-plane buckling due to their weak stiffness, even though the arch is laterally fully restrained on top chord tubes.