2. 1. A raft of size 4 m-square carries a load of 200 kN/m2. Determine
the vertical stress increment at a point 4 m below the centre of the
loaded area using Boussinesq’s theory. Compare the result with
that obtained by the equivalent point load method and with that
obtained by dividing the area into four equal parts the load from
each of which is assumed to act through its centre.
3.
4.
5.
6. 2. A ring foundation is of 3.60 m external diameter and
2.40 m internal diameter. It transmits a uniform pressure
of 135 kN/m2. Calculate the vertical stress at a depth of
1.80 m directly beneath the centre of the loaded area.
7.
8.
9. 3. A rectangular area 4 m X 2 m carries a uniform load of
80 kN/m2 at the ground surface. Find the Vertical
pressure at 5 m below the centre and corner of the
loaded area using the equivalent point load method.