Print Email Facebook Twitter Numerical Analysis of Damage Iinitiation and Development in Bends of Steel Pipelines Title Numerical Analysis of Damage Iinitiation and Development in Bends of Steel Pipelines Author Swart, A.E. Contributor Blaauwendraad, J. (promotor) Faculty Civil Engineering and Geosciences Department Structural Mechanics Date 2010-04-06 Abstract Gasses and fluids are transported via an extensive infrastructure of steel pipelines. In the design of pipeline systems the use of elbows (pipe bends) is important because their flexibility makes them able to sustain significant deformations. These bends can be subjected to permanent deformations due to various load combinations which can lead to progressive material damage. There are three stages commonly observed in ductile damage: void nucleation, growth and coalescence. When subjected to varying bending loads low cycle fatigue damage may occur. Within this research project Finite Element Analysis is used to simulate the response of pipeline bends. Two element types are implemented to model a pipe bend, the classical shell element and an efficient tube element (pipe elbow element), respectively. To predict the structural response when subjected to monotonic loading a damage model is implemented for both elements. When subjected to cyclic loading three phases can be identified. During the first few cycles the permanent deformation increases rapidly. After some cycles, the rate of permanent deformation stabilizes until the point of response degradation. In order to capture this response a new material model, based upon the afore mentioned model, is proposed. Experiments have indicated that this model is well suited to determine the point of material failure. Subject Finite ElementsPlasticityDamage To reference this document use: http://resolver.tudelft.nl/uuid:23c9f321-4d8c-480d-85fb-c7910cd79d9e Publisher A.E. Swart Embargo date 2010-05-06 ISBN 9789090252421 Part of collection Institutional Repository Document type doctoral thesis Rights (c) 2010 Swart, A.E. Files PDF Dissertation_AE_Swart.pdf 4.09 MB Close viewer /islandora/object/uuid:23c9f321-4d8c-480d-85fb-c7910cd79d9e/datastream/OBJ/view