An Effective Iterative Algorithm of the Upper Bound Limit Analysis with Slots Pipelines under Multi-loading Systems

In this paper, an effective iterative algorithm is used for the limit analysis of 3-D rigid-perfectly plastic bodies. A numerical path scheme for radial loading is adopted to deal with complex multi-loading system. The iterative algorithm has been applied to carry out the effects of slots on the upper bound limit loads of defective pipelines under multi-loading system, such as bending moment, internal pressure and axial tension. The research achievements are very useful to integrity assessment of defective pipelines.