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Extended Question: When I mesh slabs and walls at 36”-48”, there are numerous warnings which include no stiffness, negative stiffness, lost accuracy, and ill-conditioned / unstable. However, when I change the meshing option to be only at visible gridlines, the model runs without error, and forces / reactions are significantly different. Why is this?
Answer: Columns In ETABS v9 and older columns are not automatically included as meshing locations. Therefore it is important to mesh at grid lines to avoid ill-conditioning and to ensure a stable model. For ETABS 2013 (v13) and beyond, floor default meshing recognizes columns as meshing points, hence this is rarely and issue anymore
To connect meshes, what are the advantages of line constraints over mesh generators?
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