QUESTION $1$

$($a$)$ We define the hydraulic head as: $H=z+\frac{u}{{}_w}.$ Explain the meaning of this equation and how it is linked to Bernoulli's theorem.

$[3$ marks$]$

$($b$)$ An earth dam made of silty sand of permeability equal to $2\mathrm{.}4{10}^{-7}m{s}^{-1}$ is represented in Figure Q$1,$ to scale. Determine the hydraulic head in A$,$ B$,$ C$,$ D$,$ E$,$ F$.$

$[6$ marks$]$

FIGURE $1$

$($c$)$ Determine the pore water pressure in A$,$ B$,$ C$,$ D$,$ E$,$ F$.$

$[6$ marks$]$

$($d$)$ Using a flow net you will have drawn, calculate the total flow of water through the dam per day per unit metre.

$[7$ marks$]$

$($e$)$ Knowing that the dam was constructed with a void ratio $e=0\mathrm{.}70,$ what is the mean true velocity of water through the dam?

$[3$ marks$]$

QUESTION $2$

$($a$)$ A sample of soil $($soil A$)$ is retrieved from the ground to be tested. The soil is saturated. A cylindrical specimen of soil A is prepared, measuring $37\mathrm{.}9mm$ diameter and $76\mathrm{.}1mm$ height. The specimen is saturated, and weighs $164\mathrm{.}4g.$ It is then placed in an oven at $105C$ for $24$ hours to dry and weighed again; the dry mass of the soil specimen is $116\mathrm{.}7g.$ The specific gravity of the soil was determined as $2\mathrm{.}71.$