Evenly transmits load(s) to the ground the foundation rests on (subsoil) safely & eliminate damaging ground movement during construction and throughout the anticipated life of the structure
Load
Dead
Structual
Wind
Imposed
Damaging ground movement
Frost heave - caused by freezing and expanding water
Soil movement
Change in volume of water in ground - when soil wet / dry
Subsidence
Trees
Abstraction from vegetation
Weather
Bearing Capacity
Defined: Maximum Pressure of ground
Problem: Load exceeds bearing capacity
Downward movement of foundations occurs
Solution
Reduce load carried by foundation
Increase plan size of foundation to reduce load per unit area