QUESTION $1$ IS COMPULSORY

$1.$

a$)$ Explain, with the aid of diagrams, how the earth pressure on a vertical

$(15$ marks$)$

retaining wall is related to the movement of the wall relative to the retained soil.

In your answer, you should distinguish between the at rest, active, and passive states.

b$)$ List the principal modes of shear failure under shallow foundations and explain one of them.

$(10$ marks$)$

c$)$ Please describe the three parts that comprise the total settlement under a

$(10$ marks$)$

foundation

d$)$ Explain the role of the Desk Study in a site investigation.

$(5$ marks$)$

Total marks for question $1$

$40$ marks

$2.$ A building is to be placed on a strip footing $1\mathrm{.}50m$ wide, on a sand at a depth of $1\mathrm{.}20m.$ The effective shear strength parameters are ${}^{\text{'}}=26$ and $c^{\text{'}}=0$kPa, and the bulk unit weight is $17k\frac{N}{m^3}.$

The groundwater table is well below the existing ground level and does not affect the behaviour of the foundation.

The footing is being designed to support a permanent loading from the building of $175k\frac{N}{m}$ and a variable loading of $80k\frac{N}{m}.$

Using the suggested procedure in Annex D of Eurocode $7-$ Part $1,$ and applying Design Approach $1-$ Combination $2$; please:

$($a$)$ Determine the design bearing resistance for the drained condition.

$(15$ marks$)$

$($b$)$ Determine the total design vertical load acting on the foundation.

$($c$)$ Check if the design satisfies the ultimate limit state condition according to Eurocode $7.$

$(10$ marks$)$

$(5$ marks$)$

Total marks for question $2$

$30$ marks