Hello,
I am designing an isolated spread footing using ACI 318-05 with SFA Build 9.2.0.34. When designing the pedestal SFA provides an area steel of around 1% the gross area of the pedestal. However, ACI 318-05 Section 10.8.4 and 15.8.2.1 state a steel area of 0.5% the gross area may be used if the cross section is larger than required for the given factored loads.
I see from a previous post (https://communities.bentley.com/products/ram-staad/f/ram-staad-forum/199690/sfa-isolated-foundation-doesn-t-design/596308#596308) that the option to reduce this area was removed because ACI 318 removed those clauses from later versions.
However since I am designing to an older version of the code, is there a way for SFA to consider the reduced gross area of the column/reduced area of steel required per the previously mentioned sections of ACI 318-05? Alternatively, is there a way for SFA to treat the pedestal as a rigid element and not provide a design?
Thanks for your help
Unfortunately I don't think you can control the minimum reinforcement for the pedestal anymore. An alternative would possibly be to not have the pedestal and adjust the column dimensions so that these match the pedestal dimensions. However if you go that route, please make sure that additional moments due to horizontal shears at the column bases ( = shear x pedestal height ) are manually added to the column loads.
Hi Mr.Sye,
As per the summary table ( to ACI ), the stump rebar is shown like # 6 @ 5.00mm , so that means 6mm dia. bars , what the @ 5mm refers ?
There was a reporting error in the summary table in Builds 9.3.0 and older, and was corrected in the most recent release - 9.4.0.20.
Scroll down and go to the details of the shear design of the pedestal. You should find the correct value like that shown in this figure.