Question $2$

Determine the required layer thicknesses by the $1993$ AASHTO procedure for the following design conditions:

$-\backslash (\backslash$quad $\backslash )$ Rural interstate $($Assume Reliability $\backslash (=95\backslash \%)\backslash )$

$-\backslash (\backslash$quad $\backslash )$ ESALs $\backslash (=11\backslash$times $10^\{6\}\backslash )$

$-$ Design Serviceability Loss: $2\mathrm{.}0($assume standard deviation $\backslash (=0\mathrm{.}49\backslash ))$

The pavement structure will consist of three layers:

$-$ Hot$-$Mix Asphalt, Modulus of Resilience $\backslash (=450,000\backslash )$ psi;

$-$ Base layer $($untreated$)$ with a CBR $\backslash (=90\backslash \%\backslash )$;

$-$ Subbase layer $($untreated$)$ with a modulus of resilience of $17,000$ psi;

$-$ The subgrade resilient modulus is $8,000$ psi.

$-$ It takes one week for water to be drained from all layers and the pavement will be exposed to moisture levels approaching saturation level for $\backslash (30\backslash \%\backslash )$ of the time.