2D/3D modeling of concrete weight coating to understand its performance including crack development

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The objective of this work is to produce a model that predicts the performance of concrete weight coating (CWC) on submarine pipelines. Full-scale bending, shear, or impact tests to simulate the field conditions are costly and time consuming. When evaluating potential changes to the pipe manufacturing process, a model to reliably predict the impact of the changes is desired. Such a model would help to reduce the burden of full-scale testing by identifying and pre-selecting the most promising manufacturing approaches and combinations to put forward. Several variables must be accounted for, including: the aggregate and cement used, the type of anti-corrosion coating applied to the steel pipe, the type and arrangement of embedded reinforcement, and the method of concrete weight coating application (impingement or compression). All of these variables are in constant flux depending on the geographical location of the installation and the available materials/methods. A micro (µ) mechanical modeling approach is suggested based on the finite discrete element model (FDEM) technology. FDEM combines the advantages of large strain finite elements with those of the discrete elements, allowing for explicitly modelling the propagation of cracks into an originally intact material, as well as the interaction between the different phases and materials. By modelling the physical interactions at the µ-scale, FDEM is able to reproduce the response of the tested material as an emergent property of the model. A µ-characterization of CWC together with standard mechanical tests performed inside a µ x-ray computed tomography machine (µCT) will inform and constrain the development of a FDEM model.