Automatic Two-Stage Calculation of Bifurcation Path of Perfect Shallow Reticulated Domes

In this paper an attempt is made to automatically calculate the bifurcation of the buckling path of shallow lattice domes. This calculation is performed in a two-stage analysis of the space structure without introducing any geometrical imperfections. The method is implemented in a combined materially and geometrically nonlinear finite element analysis computer program based on an incremental/iterative Newton-Raphson solution procedure. In the first stage analysis, the load factors at which critical points occur are determined and the primary path is obtained. In the second stage analysis the perfect structure is lead toward the lowest bifurcation path using the technique described in this paper. The resulting theoretical predictions are verified by existing experimental observations on two model domes.