Free Response $(20$ pts$)$

The table below is results of a consolidation test on an organic soil sample from a relic Florida sinkhole that is now

overlain by sand. The initial sample height and area in the specimen box are $1\mathrm{.}9$ cm and $32c{m}^2,$ respectively. The dry

density and mass of the specimen are $2\mathrm{.}45\frac{g}{c}{m}^3$ and $119$ g $.$

$($a$)$ Plot the $e-log{}^{\text{'}}$ curve.

$($b$)$ Determine the preconsolidation pressure $(k\frac{N}{m^2}).$

$($c$)$ Calculate the compression index, $C_c.$

$($d$)$ Determine the overconsolidation ratio of the specimen if the average in situ effective stress in the middle of

the organic layer was determined to be $33\mathrm{.}2k\frac{N}{m^2}.$

$($e$)$ Calculate the settlement from one$-$dimensional primary consolidation of the $4$ m $-$thick organic deposit for

$e_0=0\mathrm{.}252,C_s=0\mathrm{.}1C_c$ and a change in effective stress of ${}^{\text{'}}=50k\frac{N}{m^2}.$

$($f$)$ Evaluate the results and characterize the organic layer. $($Be succinct$)$