PROGRESSIVE FAILURE ANALYSIS OF INELASTIC SPACE TRUSS STRUCTURES

In general, the progressive failure analysis of space truss systems ca n only be adequately evaluated with both material and geometric nonlin earities considered. This paper utilizes constitutive relationships to provide the fundamental modeling of elastic and inelastic member beha vior, coupled with a geometrically nonlinear finite element model. Mod eled member material behavior modes include: buckling, yielding, inela stic post-buckling, unloading, and reloading. Geometric nonlinearity i s based on iteratively correcting the linearized updated Lagrangian sp ace truss displacement equations. Interaction of the nonlinear loading behavior results in structure force redistribution which can lead to member failure, unloading, or reloading. Such behavior can lead to the progressive failure of a space truss structure. The developed model t races the sequence of localized buckling, yielding, and inelastic memb er response. Results are presented to demonstrate model capabilities f or representing the inelastic, progressive failure response of space t russ structures.