Click 
(Load definition) or select RC element > Loads to define the loads applied to a foundation.
This image presents the dialog for geometry type with spread footing for two columns selected. Several load natures are available: dead, live, snow, wind, seismic, accidental, temperature and design. Subnatures vary depending on a selected RC design code and the load case nature. Three load types are available:
Axial load.
Load with a normal force, a bending moment, and a shear force.
Load with a normal force, a bending moment and a shear force acting in two directions.
Depending on the load selected, appropriate fields to define the force values will appear:
- N - the vertical N force value for foundation loads
- Fx - the cross-sectional force value Fx. Available when the foundation is loaded with a normal force, a bending moment, and a shear force
- Fy - the cross-sectional force value Fy. Available when the foundation is loaded with a normal force with a bending moment and a shear force acting in two directions
- Mx - the bending moment Mx. Available when the foundation is loaded with a normal force, a bending moment, and a shear force
- My - the bending moment Mx. Available when the foundation is loaded with a normal force with a bending moment and a shear force acting in two directions.
In the case of foundation with two columns, a set of forces applied to both foundation piers is defined for each load case. These forces correlate with each other and principles of force combinations do not apply.
Available load categories contains two items: the foundation load (resulting from one or two columns) and the backfill load. The dialog in which the backfill load may be defined is shown below.
In the case of a backfill load, the value of the load Q1 should be entered. Two natures are available: dead and live.