Limit and shakedown analysis of pressurized pipelines containing defects

In this paper, the integrity assessment of pressurized pipelines containing defects is performed by direct simplified methods of limit and shakedown analysis. The defects considered are part-through slots of various geometrical configurations. The engineering situation considered here has practical importance in the pressure vessel and pipe industry. The results are compared with those obtained by a step-by-step procedure using the professional code ABAQUS and where possible, with those provided by semi-empirical formulae used in engineering. The simplified methods are found more economical and more reliable than marching solutions achieved by step-by-step evolutive elastic-plastic analysis. The effects of various part-through slots on the load-carrying capacities of pipelines are investigated. The project was supported by the National Science and Technology Commission of China and by the Department of Structural Engineering, Technical University of Milan, Italy