COMPLETE THE WHOLE B PART, I HAVE GIVEN SOLUTION FOR A

Now calculate the total stress, pore pressure and eftective stress

at different depth.

At section $1-1$

${}_{1-1}=0,u_{1-1}=0,{}_{(1-1)}^{\text{'}}=0$

At section $2-2$

${}_{2-2}=319\mathrm{.}62+120\mathrm{.}928=79\mathrm{.}788k\frac{N}{m^2}$

$u_{2-2}=0k\frac{N}{m^2}$

${}_{(2-2)}^{\text{'}}=79\mathrm{.}788k\frac{N}{m^2}$

At section $3-3$

${}_{3-3}=31\mathrm{.}9\mathrm{.}62+120\mathrm{.}928+517\mathrm{.}32=166\mathrm{.}388\frac{kN}{m^2}$

$u_{3-3}=59\mathrm{.}81=49\mathrm{.}05\frac{kN}{m^2}$

${}_{(3-3)}^{\text{'}}=166\mathrm{.}388-49\mathrm{.}05=117\mathrm{.}338k\frac{N}{m^2}$

$At$ section $4-4$

${}_{4-4}=319\mathrm{.}62+120\mathrm{.}928+517\mathrm{.}32+819\mathrm{.}798=3$:

$u_{4-4}=139\mathrm{.}81=127\mathrm{.}53\frac{kN}{m^2}$

${}_{(4-4)}^{\text{'}}=324\mathrm{.}7-127\mathrm{.}53=197\mathrm{.}17\frac{kN}{m^2}$

At section $4-4$

${}_{4-4}=319\mathrm{.}62+120\mathrm{.}928+517\mathrm{.}32+819\mathrm{.}798=3$:

$u_{4-4}=139\mathrm{.}81=127\mathrm{.}53\frac{kN}{m^2}$

${}_{(4-4)}^{\text{'}}=324\mathrm{.}7-127\mathrm{.}53=197\mathrm{.}17\frac{kN}{m^2}$

$($b$)$ i$)$ At a depth of $12$ meters, we need to determine the principal stresses. For this, we use the lateral

stress ratio $(K)$ which is the ratio of horizontal stress to vertical stress. Given $K=0\mathrm{.}6,$ we can calculate

the principal stresses.

ii$)$ We also need to find the orientation of the planes where the shear stress is maximum. This

involves determining the angles of these planes relative to the horizontal plane and sketching them.

iii$)$ At the same depth $(12$ meters$),$ we calculate the maximum shear stress and the shear$-$to$-$normal

stress ratio.

iv$)$ Finally, we plot Mohr's circle to represent the stress state at this depth. This includes indicating

the points representing the principal stresses and the maximum shear stress.