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W.Salaaam Waqas ! 1) No ! you are not missing anything.... 2) choose the 3rd option in Loads to export ...(have a look to the attached screenshot) 3) Yeah Soil support value matters in soil pressure because high modulus of sub grade value means more stiffer is the soil and hence more will be the soil pressure. 4) Your value is OKKY but I usually take the safty factor 2.5 (average of 2 & 3) because safty factor is 2 for granular soil & 3 for cohessive soil. (0.75x2.204x1000x2.5x12=49590 pcf) 5) i would model it as a single footing slab, so it will act as combined footing....

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.

Load which is applied to MEMBRANE objects transfers directly to supporting structural objects i.e beams, whereas SHELL objects have bending stiffness and therefore resist a portion of the load through flexural deformation. As a result, less load will be available to transfer to beams located under a shell, while 100% of the load will transfer through a membrane. SO in membrane type slab case your B/C joint capacity exceeds the limit because you need more strong joint than that of the SHELL type slab case. If you are assigning the slab as Membrane and want to overcome the joint capacity failure so either increase the column size or reduce the beam size.....