Hi,
I'm literally confused of this table of what should be done. I'm using version 8.4.1.24, When I ticked the "Include" box for DL primary case and all service and ultimate load cases, warning is showing in the analysis results saying that applied selfweight is more than total weight of all structural elements. So I unchecked all box but primary DL. With this I'm not getting any warnings. Is that right or should I include all service and ultimate cases?
If I want to use 0.6DL combination, can i just change the dead weight factor to 0.6 without ticking the "Include" box
I have pedestals/piers in my model and given the sizes and height under "Pedestal and anchor bolt" section. But I'm not sure if the pedestal selfweight has been considered into the analysis
Another question is Do I need to modify the dead weight factor to include the soil weight above the mat? I have given the value on the soil property. Will this taken into the account for the selfweight of the soil without modifying the dead weight factor?
My calculation sheet after analysis shows as under for the soil details; soil height above mat is 2 ft, soil density is 120 lb/ft3, but applied load due to soil is 0.22 kip/ft2 instead of 0.24 kip/ft2. Please clarify
Thanks
You need to check the Include for load case 1 ( DL ) and all the service and the ultimate cases. The warning in the analysis output file is only because of the fact that the software is accounting for the soil weight through an additional selfweight command ( appropriately factored). You may simply ignore the warning.
If you DO NOT check the Include box the selfweight will not be included. So to get 0.6XDL you should check the include box and specify the Dead Weight factor as 0.6.
Selfweight of the Pedestal for mat foundation jobs are not automatically included. Please account for that by applying an additional column reaction load.
To account for the soil weight, just specify the soil height and the density and the software would include the weight due to the soil in all cases for which selfweight is included.
Regarding the applied load for soil reported in the calculation sheet, please double check if you have used a dead weight factor other than 1 ( say 0.9 ) for the DL in the Add Selfweight table or not ( although your first screenshot shows a factor of 1 but my guess is, it was modified later to 0.9). If not please upload the model and we will look into it.