Figure $1$: Cross$-$section through homogeneous earth fill dam.

The earth dam shown in Figure $1$ is to be built on gravelly sand. The dam will

extend a distance of $250m$ perpendicular to the cross$-$section $($i$.$e$.,$ out of the

page$).$ Redraw the above cross$-$section to a scale suitable for $\frac{81}{2}"{11}^{\text{'}\text{'}}$

paper in "landscape" orientation and draw a flow net assuming the dam is

essentially impermeable $($although in reality no soil is truly impermeable, but

only has a very low $k).$

Provide the flow net.

Compute the flow rate $(Q).$

Identify the area in the flow net that has the greatest hydraulic gradient

$($i$).$

Use the finite element software Slide to carry out a seepage analysis for the

conditions shown in Figure $1$ assuming the dam is impermeable $($use a very low

value of $k$ in your model$).$

Provide Slide output showing the following all on a single image:

contours of total head; flow lines; vectors of seepage velocity; and the

piezometric surface.

Compute the flow rate $(Q).$

Identify the area in the flow net that has the greatest hydraulic gradient

$($i$).$

How do the results compare with the graphical flow net developed for

Question $1?$