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Reinforcement of Concrete Structures with Mecway and Paraview

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Background Unlike the FreeCAD FEM work bench, Mecway does not have the capability of estimating the level of reinforcement required in a concrete structure to prevent brittle failure under tension or shear. To overcome this limitation, I developed a Paraview script based on the method described in "Computation of reinforcement for solid concrete", P.C.J. Hoogenboom and A. de Boer, HERON Vol. 53 (2008) No. 4 . This is the same routine implemented in FreeCAD. The script calculates the principal tensile stresses in the concrete from an elastic analysis and uses those to determine the minimum reinforcement in the three coordinate directions required to prevent failure. In the analysis it is assumed that the concrete material cannot carry tensile stresses, whereas the steel is utilized to its maximum capacity (i.e. reaches yield). Further details of the methodology and its application can be found in this post Workflow The workflow to display the reinforcement ratios rhox,...
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Conceptual Design of Concrete Structures with FreeCAD and Paraview

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Background The FreeCAD FEM work bench has the capability of estimating the level of reinforcement required in a concrete structure to prevent brittle failure under tension or shear. This is done with the method described in "Computation of reinforcement for solid concrete", P.C.J. Hoogenboom and A. de Boer, HERON Vol. 53 (2008) No. 4 . In essence it is a post processing routine for Calculix, which calculates the principal tensile stresses in the concrete from an elastic analysis and uses those to determine the minimum reinforcement in the three coordinate directions required to prevent failure. In the analysis it is assumed that the concrete material cannot carry tensile stresses, whereas the steel is utilized to its maximum capacity (i.e. reaches yield). The required reinforcement is expressed in terms of a reinforcement ratio. This is the ratio of steel to concrete area. For example a reinforcement ratio of 0.01 in x-direction (rx=0.01) means that the total c...
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Post-processing of Finite Element Results with FreeCAD and Paraview

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Introduction Some FreeCAD forum posts and tutorials use Paraview (PV) to review and analyse FreeCAD FEM Workbench results. This post explains the basics of transferring data from FEM Workbench to PV and shows some of the options and settings for displaying data. Prerequisites FreeCAD version 0.19 or higher. Paraview downloaded directly from it's website or your preferred package manager. This post is based on Paraview version 5.8.0 for Windows, which was the most recent version at the time of writing the post. The FreeCAD files used for this post available in this and this FC forum thread. Data Transfer from FEM workbench In FEM workbench highlight the CCX_Results object. Next, use menu option File > Export > FEM result VTK (*.vtk *.vtu) to export the VTK data. Data Import in Paraview The start-up screen shows an empty Pipeline Browser. This is where the imported VTK data objects and applied filter objects (for geometry or data) will be visible. Use menu o...
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