Problem $2(60$ points$)$

You are evaluating the geotechnical characteristics of a Miami site for a proposed office building. Subsurface investigation showed that the site consists of the following layers: $(1)$ a $5-$ft sandy layer with a unit weight of $100$ pcf ; $(2)$ a $10-$ft silty sand layer with a saturated unit weight of $115$ pcf; $(3)$ a $20-$ft saturated clay layer with a unit weight of $118$ pcf$,$ void ratio of $0\mathrm{.}85,$ and underlain by gravels. The site seemed to have strong potential for undergoing consolidation settlement. Therefore, you collected samples from the clay layer and performed a consolidation test. The pre$-$consolidation pressure for the clay was known to be $1\mathrm{.}0$ tons $\backslash (/\backslash$mathrm$\{$ft$\}^\{2\}\backslash ).$ The ground water table is at the level of the second sand layer. Some of the data points from the test are as follows:

Effective Consolidation Pressure$($tsf$)$

Void Ratio

$1\mathrm{.}03$

$1\mathrm{.}01$

$\backslash (0\mathrm{.}85$ e$\_\{\backslash$circ$\}\backslash )$

$0\mathrm{.}75$

To expedite the consolidation process and achieve stability, a fill material was brought in from another location and placed on the site. This fill material was a sandy soil with a unit weight of $110$ pcf and its thickness was $\backslash (5-\backslash$mathrm$\{$ft$\}\backslash ).$

Perform the following tasks:

$1.$ Draw a schematic of the subsurface conditions including all the properties.

$2.$ Draw the distribution of total stress, pore water pressure and effective stresses. Justify your answer.