Effective Stress $(20$ points$)$

Consider the site shown below.

For the three scenarios described below, plot the distribution of total stresses, pore pressures, and effective stresses with depth $($z$)$ form the ground surface up to a depth of $25$ m :

a Assuming hydrostatic conditions

b When a piezometer installed at the top of the gravelly sand layer indicates that the water inside it rises to $1$ m below the ground surface

c At time $=0^{-},$ time $=0^{+},$ and six month after a developer adds a fill of sand on top of the clean sand to raise the ground surface elevation. The added fill is $4$ m in thickness, and it has a total unit weight of $16k\frac{N}{m^3}.$ Assume consolidation takes place immediately in the silt.