Failure of Cylindrical Shells: Numerical and Experimental Study
In industrial structures, the presence of cracks under critical loads leads to complete ruin. Fracture mechanics allows the study of macroscopic defect damage. This requires the knowledge of the stress fields and the deformations near the crack. Our work is an application of fracture mechanics into the domain of the pressurized structures with defects. Design of this type of structures is subjected to standards, codes and regulations driven by the potential risks which they represent. The knowledge of the pressure limit in these structures allows respecting the safety domain. We present in this paper the numerical solutions and experimental results for stress distribution at defect tip. The structure's elastic and elasto-plastic modelling will be treated by the finite element simulation. In the elastic case, we study the influence of the geometrical parameters for axial and circumferential cracks and determine the elastic integral J. Measures of strains near defects in the studied model have been made by strain gauges. The experimental results validate the numerical simulations. In addition, acoustic emission is used to define sensitive zones and to control defect evolution during the test until failure in the structure.
Keywords
fracture mechanics pressure vessels numerical solutions experimentsPreview
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