CAUSES OF FOUNDATION SETTLEMENT

Settlement of foundations may be caused due to the following reasons:

1. Elastic compression of the foundation and the underlying soil.
2. Plastic or in-elastic compression of the underlying soil.
3. Ground water lowering is another major cause for settlement. This is more adverse in granular soils due to repeated raising or lowering of the ground water. In clayey soil prolonged lowering of ground water may cause settlement.
4. Vibrations caused by pile driving, machinery, blasting, etc. This is more adverse in granular soils.
5. Other causes of settlement include volume change of soil, ground movement and excavation for adjacent structures, mining subsidence, etc.