The Effect of Support Stiffness on Buckling and Post-Buckling of Imperfect Plane Arch Trusses

This paper presents a study on the effects of support stiffness on buckling and postbuckling of imperfect plane arch trusses. A imperfect plane truss element model considering large displacements is constructed based on the Updated Lagrangian formulation. This truss element model is used for buckling and postbuckling analysis of a plane arch truss with consideration of support stiffness, in order to investigate the effects of support stiffness on the overall stability of plane arch trusses. Some notable results presented herein include: (1) the relationship between critical load and support stiffness, (2) the load – displacement curves corresponding to different values of support stiffness, (3) the effects of imperfection on postbuckling of trusses. Two examples of plane arch truss are described and the results have been verified against the results of previous studies for a special case (i.e., rigid supports). This study shows that the effects of support stiffness on buckling and postbuckling of imperfect plane arch trusses is very significant and should be taken into account in the analysis of trusses considering large displacements.