$3.$

a$.$ Data from an oedometer test are given in Table Q$3.$ The water content at the end of the test is $\backslash (20\mathrm{.}88\backslash \%\backslash )$ and the specific gravity of the soil particles is $2\mathrm{.}75.$

i$.$ Calculate the final void ratio.

$[2$ marks$]$

ii$.$ Calculate the initial void ratio.

$[3$ marks$]$

iii. Calculate the void ratio at every other pressure increment

$[5$ marks$]$

iv$.$ Plot a well$-$labelled graph of the void ratio against the natural logarithm of the vertical effective stress.

$[5$ marks$]$

v$.$ Explain the shape of the plot in $($iv$)$

$[2$ marks$]$

Table Q$3$

b$.$ Explain, with the aid of a well labelled diagram, how the total pressure, pore water pressure, and effective stress change with an increase in load during consolidation.

$[8$ marks$]$