IN$-$SITU TESTING CORRELATIONS

Using the empirical correlations available between SPT blow count along with normally consolidated soil properties of relative density $(D_r)$ and internal friction angle $({}^{\text{'}}),$ please calculate the suitable design parameters as a range.

Effective overburden pressure at testing depth: $200$ kPa

$N_{50}=25$

Use the equations given below, and the graphs from the handouts provided $[$i$.$e$.,$ Gibbs and Holtz $(1957),$ Bazaara $(1967),$ Stroud $(1988),$ De Mello $(1971),$ Schmertmann $(1975)].$

Skempton $(1986)$: $\frac{N_{70}^{\text{'}}}{D_r^2}=32+0\mathrm{.}288P_o^{\text{'}}$

Bowles $(1996)$: ${}^{\text{'}}=28+0\mathrm{.}15D_r(\%)$

Japan Railways: ${}^{\text{'}}=(18N_{70}{)}^{\frac{1}{2}}+15$

${}^{\text{'}}=0\mathrm{.}36N_{{70}^{\text{'}}}+27$

${}^{\text{'}}=0\mathrm{.}45N_{{70}^{\text{'}}}+20$