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User may define a new coordinate system for practicality.
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Example 1
Internally Pressured Cylinder: Surface Forces
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Cylinder divided into 16 different orientations to be represented in FEA.
Each of coordinates systems are created according to those new orientations so that Z direction always act as normal direction for corresponding surfaces.
Nodes are assigned to corresponding coordinate systems.
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Surfaces defined are automatically acts upon their related node orientations.
Surface forces can be seen in figure below.
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By defining required node orientations primarily, users are freeing themselves from calculating perpendicular orientation one by one for every single.
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Example 2
Three Span Skewed and Curved Bridge : Bearing Rotations
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Pier orientations and bridge curvature can be seen from the model above.
Some bearings for this structure should restrict movements tangent to the bridge at their location. Hence, bearing elements for the bridge have to be oriented accordingly.