Geometry
Effective depth d = t − cover − 0.5 (assumed #8 bar). 3 in cover is typical for concrete cast against earth (ACI 20.5.1.3).
Loads
Unfactored, kips, compression positive. The engine runs the full ASCE 7-22 §2.4 set for bearing and §2.3 set for concrete design and reports which governs.
Both combinations done by hand, outside the tool. A Pu/P ratio no ASCE 7 gravity combination can produce is flagged.
Materials & soil
Net allowable bearing from the geotech report. qa is compared at service level per ACI 318-19 §13.2.
Results
Section
Design checks ACI 318-19
Reinforcement each way, bottom mat
Required As = in² (ρ = ). Options providing at least that:
How this is calculated
Formula chain with code citations
Run a check to see the chain.
Assumptions carried by the engine: square interior column (βc = 1, αs = 40 per §22.6.5.2), #8 bar for effective depth, Grade ≥ 60 shrinkage steel (ρ = 0.0018, §24.4.3.2). Eccentric loads, rectangular footings and overturning are desktop features.