Summary: | The aim of this study is to propose a theoretical frame that is able to lead someone to an appropriate way of modeling cementbased material extrusion. It clearly appears that different extrusion scenarios may occur. Cement-based materials are viscoplastic materials that may undergo drainage during an extrusion process carried out at low velocity. Four material behaviors can be encountered: perfect plastic, viscoplastic, frictional plastic (with evolving properties) and frictional viscoplastic (that has never been reported in the literature as drainage occurs when ram velocity is low and thus when viscous effects can be neglected). In this work, criteria are proposed to choose the more relevant way to model extrusion. Then, models are proposed for the possible extrusion scenarios.
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