# Create 2D Face to Ground Contact

It can be convenient to model a foundation stiffness under a mesh of 2D elements. This tool creates a set of springs and constraint equations to model this interaction

# Definition

Elements

For each 2D element in the element list, a node will be created at the element centre and that node will be connected to the 2D element by a constraint equation.

Stage

The stages to which this constraint should apply.

Springs

The centre node will optionally have a soil spring specified by a nodal stiffness property.

Raft Interaction

If this is to be used for a soil-structure interaction the relevant raft interaction areas can be determined.