Do I need to put separate slab edges on gable roof planes on opposite sides of a ridge, and if so, then is there a trick to getting this done? I can put in one perimeter of slab edges, with one of the four edges coinciding with the beam at the ridge, but when I input the perimeter for the opposite side of the ridge (with one edge "sharing" a joist framing member) at it's perimeter, the first slab disappears. The deck assign command is greyed out indicating that there is no closed slab perimeter. I am working on a large (925ft x 440 ft) industrial building with a ridge parallel to the long dimension - not centered, but essentially it is a gable roof. First I put the slab edge in one piece, ignoring the gable geometry, and that appears to work fine for the RAM Steel module and gravity loading, but I had uncertainty when I got to RAM Frame, causing me tho think that I had to divide the slab edge at the gable ridge. Incidentally, there is an roof expansion joint, with double columns and beams - no apparent problem with putting a gap in the model there. Thanks for considering this question.
You need two deck polygons to define a gable roof with two slopes, but a single, all-encompassing slab edge loop is fine. Refer to https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/3432/ramss-modeling-faq and https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/7207/ram-ss-3d-viewer-faq
Answer Verified By: WILLIAM MOORHEAD