Your XLS might calculate 0.1% steel. That is too low for a crane foundation. Minimum flexural reinforcement is 0.18% for Grade 60 steel. Punching shear often drives the required steel to 0.5%–1.0%.
A standard engineering workflow for a gravity pad footing involves several sequential checks. Your Excel spreadsheet should automate these steps chronologically: Step 1: Geometry and Material Input Define the initial dimensions of the concrete pad (Length ) and material properties (concrete compressive strength fc′f sub c prime , steel yield strength , and soil allowable bearing capacity qallq sub a l l end-sub Step 2: Stability and Soil Bearing Pressure Tower Crane Foundation Design Xls
Where: