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- Eccentricity – For rigid diaphragms, the accidental eccentricity associated with auto seismic loading is concentrated and applied at the center of mass, whereas for semi-rigid diaphragms, accidental eccentricity is applied to every node for auto seismic loads. If no diaphragm is assigned eccentricity will not be applied to any node. For auto wind load cases and rigid diaphragm , load loading is applied at geometric centroid, in case of semi-rigid diaphragm auto wind loads are distributed in 10 nodes, so that the summation summation of these forces with respect to centroid will be equivalent to lateral and torsional wind cases.
- Reporting forces – In-plane chord, shear, and collector forces are only reported when using semi-rigid diaphragms.