Q. Show the Settlement due to Excavation?

If  an excavation is made in a sandy soil,  the structure founded near the excavation will be affected and it will cause extra settlement. The settlement due to excavation of the cut will not extend beyond a distance equal to the depth of cut. For example,  if  the depth of cut is 5m, then the building at a distance of 5 m from the excavation  only will effect. This can be minimised by adequately providing the bracings.

When any cut is made in soft clay stratum,  the structure loaded at the sides of  the cut acts like a surcharge. Therefore  the clay near the bottom of the cut yields laterally towards the excavation under this surcharge. Hence, the ground surface above  the yielding clay starts settling.