Singh, Mansa C.Gupta, Padam P.2005-07-212005-07-211980Gupta, P. P. (1980). A Study of the crack propagation in backfilled and unbackfilled pressurized gas pipelines (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/24482NL Number: 51265http://hdl.handle.net/1880/21969Bibliography: p. 89-92.Shear fractures can propagate over a considerable distance in pressurized gas pipelines. This has been demonstrated by experimental tests performed by Battelle Memorial Institute. An understanding of the phenomenon is sought in order that a suitable design criterion can be adopted to prevent such failures. Experimental test results have been used to gain an insight into the phenomenon, and also to provide data by which theoretical solutions can be judged. The theoretical treatment in this thesis is based upon a balance between the energy supplied by the exhausting gas pressure, and that dissipated as fracture and kinetic energy. The energy terms are evaluated separately for bulge and flap portions of a fracturing pipe. The development of the balance requires a detailed understanding of gaseous decompression, pipe deformation and shear fracture extension. Based on the energy balance, the conditions for crack arrest are established for the suggested model and two other existing models. These conditions are in terms of a non-dimensional energy ratio which discriminates between propagation and arrest behaviour. Arrest data is used to verify the validity and correctness of the three models. Finally, energy equations are established for backfilled pressurized gas pipelines.xvi, 98 leaves : ill. ; 30 cm.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.TA 409 G85 1980 FicheFracture mechanicsGas, Natural - Pipe linesGas, Natural - Pipe line failuresmaster thesishttp://dx.doi.org/10.11575/PRISM/24482TA 409 G85 1980 Fiche