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Assalam o alaikum. I have been doing calculations of foundations manually. I m new user of SAFE. I have not used it for any practical project yet so i m not sure whether i m doing correct modelling or not. Kindly correct me if I am doing wrong/missing some step. 1) I made an ETABS model with its based as fixed. (because my site is in Quetta zone 4 (SDC E) so i cant model base as pinned because lateral drift exceeds limits) 2) After running model, I exported base of project by EXPORT MODEL---> TO SAFE V.12 F2K ---> Selected Story is BASE and Selected option is LOAD FROM AND ABOVE ALL FLOOR and selected load cases ALL (because i needed all) 3) Then I imported model into safe. It imported all load cases, along with all load combos. 4) The after defining material, soil properties and slab frames (as footing), I assigned slabs to relevant points. 5) I assigned design strips in X and Y direction to the slabs and I assigned SOIL SUPPORT to the slabs in the way that SELECT SLAB-->ASSIGN SUPPORT DATA-->SOIL SUPPORT--->SELECT SOIL----OK 6) Now I dont need to assign any thing further because SAFE is meshing slabs automatically at max size of 4ft. 7) I just did RUN the project and then RUN DETAILING option. 8) Only step left is to read results of analysis and design. My confusions: a) Whether am i missing some steps? b ) Are, in this way, Load sizes (i.e. column sizes for shear checks and bending moment etc) also imported? c) Does soil support value matters in determining soil pressure under footing?? Or it just comes to importance when determining deformations under footing?? d) my bearing capacity is 0.75 tsf = 1650 psf so tentative value of my Modulus of sub grade is 1650x12x3 = 59400 pcf.... Am I right?? here 3 is FOS to convert allowable bearing capacity to ultimate bearing capacity. 12 is to convert inch to ft. so my final value is 59400 pcf. Am i right? e) If I model two slabs with ONE EDGE of both matching. Will SAFE automatically treat these two slabs as one and will mesh them?? Thanks.

If the aspect ratio (span/depth) of your coupling beam is greater than 4, then model it as line element in ETABS. If aspect ratio is less than 4, then model it as area element in ETABS. Diagonal shear reinforcement is most effective if the aspect ratio is less than 2. However, code does permit its use for aspect ratios between the 2 and 4, as well. If you do not require special structural wall, you can override shear strength reduction factor: you can change it from 0.6 to 0.75. If the coupling beam still fails, tweak the structural system to lower the demand on that shear wall.

W-assalam! The following article, titled 'Rust, Mill Scale and Other Surface Contaminants on Steel Reinforcing Bars' (Technical Note ETN-M-5-14), and available at CRSI web site, free of cost, may be helpful in this regard. https://netforum.avectra.com/eweb/shopping/shopping.aspx?pager=0&site=mycrsi&webcode=shopping&shopsearchcat=merchandise&productcat=technical+documents&prd_key=e5dd0e93-d499-4927-8a53-10919f8b9b6f Note: If you are a visitor and not a registered user, you will have to register for the site first, using 'New Visitor Registration' link given below, to download the article: https://netforum.avectra.com/eweb/DynamicPage.aspx?)Site=myCRSI&WebCode=Verify Regards.

How about you model it as a spandrel - assign spandrel label and design crazy cross diagonals if required. Thanks.

You cannot just assume the base fixed to control drift. Make sure actual site conditions are okay for that. Rest is perfect as Junaid said.