In some outputs for column base design, a purple area is present in the side view soil pressure diagram. What this purple area represents can cause confusion.
The values displayed in the side view is the maximum pressure, and not an average of the -Y and +Y.
If there is a larger pressure difference between the -Y and the +Y side of the minor axis, the diagram will display two colours. The diagram uses the two colours to help you visualise the three-dimensional shape of the soil bearing pressure.
· The green represents the pressure on the edge with the highest pressure
· The purple represents the edge with the lowest pressure. Hence purple is not necessarily on the uplift side, but rather the edge with the lowest positive pressure.