Causes of settlement

Foundation may settle due to the following reasons:
                  * Static loading
                  * Deterioration of foundation
                  * Mining subsidence
                  * Seasonal swelling and shrinkage
                  * Vibrations,etc.
Some of the causes for differential settlements are the following:
                  * Geological and physical nonuniformity of the soil medium.
                  * Non uniform pressure distribution from foundation to the soil due to nonuniform loading of the foundation.
                 * Water regime at the construction site.
                 * Over stressing of the soil by heavy structures built next to light ones.
                 * Unequal expansion of the soil due to excavation for footings.
                 * Non uniform disturbance of soil due to freezing, thawing, swelling and softening and drying of soils.