https://communities.bentley.com/products/ram-staad/f/ram-staad-forum/235744/error-member-3-is-not-a-valid-cold-formed-steel-section-e-10---in-staad-proHi Staad master sirs, I’m Trying with the Staad.pro model of a Rack system with Economic solutions - which consists of Hot Rolled Sections + Cold-Formed Steel sections, by using IS800 + IS801. My entire members are only supposed to be Designed as Hoten-USTelligent Community 12https://communities.bentley.com/thread/732380?ContentTypeID=1Sun, 18 Sep 2022 23:56:56 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:23a0b5e2-98e6-4cf9-a5bf-d5bb75d7c698S Thirumarainathan<p>Thanks, Mr&nbsp;<span>Abhisek</span></p><div style="clear:both;"></div>https://communities.bentley.com/thread/732371?ContentTypeID=1Sun, 18 Sep 2022 19:42:29 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:242d6f03-0897-4b1d-ba8f-7d518352cd94Abhisek M<p>In your model you have used SELECT OPTIMIZED and by default it applies to all members in a model. But, as number 3 member is not a cold formed section, it is throwing such error.</p> <p><img src="/resized-image/__size/320x240/__key/communityserver-discussions-components-files/5932/pastedimage1663530066666v1.png" alt=" " /></p> <p>I would suggest using Select instead of select optimized in this case to avoid errors. See below link for details.</p> <p><a href="/products/ram-staad/f/ram-staad-forum/107867/correct-usage-of-select-and-select-optimized-parameters">https://communities.bentley.com/products/ram-staad/f/ram-staad-forum/107867/correct-usage-of-select-and-select-optimized-parameters</a></p> <p></p><div style="clear:both;"></div>