Develop flexible pavement design for the following condition using the AASHTO

method with layered analysis approach for the determination of each layer

thickness:

Two$-$way ESAL values for the design period: $25$ million

Directional distribution of the traffic; $55-45$

Number of lanes for each direction: $2($this means all trucks will be in outside

lane.$)$

Initial PSI: $4\mathrm{.}3,$ Terminal PSI: $2\mathrm{.}5$

$M_R$ values: $9,000$ psi

Reliability level of $90\%$ with a standard deviation of $0\mathrm{.}35$

Elastic modulus of asphalt material is $300,000$psi.

Crushed stone $(M_R=30,000$psi$)$ will be used for the base layer.

Granular material $(M_R=15,000$psi$)$ will be used for the subbase layer.

Use $1\mathrm{.}0$ for drainage coefficient for all layers.