Usually, in real life you will rarely find a Spread foundation with just a Concentrated load or even with uni-Axial Bending moment.

Moments might be neglected, and not included in Calculations, but there are cases where foundations are subjected to large moments in both directions and the calculation became quite complex and difficult.

The cases when the eccentricity fall inside the Kern, the entire foundation will remain under compression and bearing pressure will be easy calculated by using the following general expression:

q = P/A ± Mx/Sx ± My/Sy

When large Bi-axial moments applied, the eccentricty fall outside the Kern, which make the calculation very complex as the above formula won't be applicable anymore.

A Portion of foundation will be under compression, and the other portion will be under Tension.

Pure Math calculation will be made to get the volumes of compression areas, Gravity Centers at critical sections.

In This way, Bending moments and Shears will be calculated, and based on that, reinforcement in each side will be calculated.

What this application can offer

Slides showing Effective area under compression & Tension areas, Volumes and Gravity Centers for both Bending Moments and Shears, Reinforcements for footing, dowels and development lengths.

Comprehensive PDF report containing information about foundation, Reinforcement distribution in Plan and in Section, Bar Bending Schedule with the total rebars required for the fondation.