$($c$)$ A Dilatometer Test $($DMT$)$ is conducted in a soil deposit at $11$ m below the ground surface level $($GL$).$ The groundwater table is at the GL$.$ The unit weight of the soil deposit is $18k\frac{N}{m^3}.$ The unit weight of water ${}_w=9\mathrm{.}81k\frac{N}{m^3}.$ From the DMT measurement it is found that A pressure is $0\mathrm{.}425$ MPa and B pressure is $1\mathrm{.}01$ MPa $.$ Given that the membrane stiffness corrections at deflections of $0$ mm and $1\mathrm{.}1$ mm are $0\mathrm{.}025$ MPa $($suction$)$ and $0\mathrm{.}03$ MPa $($compression$)$ respectively, estimate the shear strength of the soil and OCR. Classify the soil type at the level of the DMT testing.

$(9$ Marks$)$

Note: Dilatometer Test

Lift$-$off pressure $p_0=A+A$

Expansion pressure $p_1=B-B$

Material Index $,I_D=\frac{p_1-p_0}{p_o-u_o}$

$I_D<mn>0</mn><mn>.</mn><mn>6</mn>$ Clays; $,I_D>1\mathrm{.}8E_D=34\mathrm{.}7(p_1-p_0)K_D=\frac{p_o-u_o}{{}_{vo}^{\text{'}}}{C}_U=0\mathrm{.}22{}_{v0}^{\text{'}}(0\mathrm{.}5K_D{)}^{1\mathrm{.}25}$OCR$=(0\mathrm{.}5K_D{)}^{1\mathrm{.}56},0\mathrm{.}6$ Silts; $,I_D>1\mathrm{.}8$ Sands

Dilatometer modulus $E_D=34\mathrm{.}7(p_1-p_0)$

Horizontal Stress Index $K_D=\frac{p_o-u_o}{{}_{vo}^{\text{'}}}$

Fine$-$grained soil:

Undrained shear strength $C_U=0\mathrm{.}22{}_{v0}^{\text{'}}(0\mathrm{.}5K_D{)}^{1\mathrm{.}25}$

OCR$=(0\mathrm{.}5K_D{)}^{1\mathrm{.}56}$