Question $4$

$4\mathrm{.}1$ Calculate the total E$80$s of the below truck. Assume a damage factor of $4\mathrm{.}0$

$4\mathrm{.}2$ The sketch below shows the timing, initial traffic loading and traffic growth factors of a road project in the Southern African region.

$4\mathrm{.}2\mathrm{.}2$ Conduct sensitivity analysis by considering annual traffic growth rates of $6\%$ and $8\%$ during SDP$.$ Also provide a comment on your result.

$(8)$

$4\mathrm{.}2\mathrm{.}3$ What type of maintenance will be needed by the end of the year $2041?$

$4\mathrm{.}3$ Soil samples were obtained at $100$ m intervals for a newly planned category $($B$)$ road in a wet region. The measured CBR values are $10,12,11,11,9,11,13.$ Calculate the design CBR and provide a neat, labelled freehand sketch showing your subgrade design.

$4\mathrm{.}4$ Use TRH$4$ method to provide all possible alternative pavement structures for a road category C planned in a wet region. The cumulative traffic over $15$ years SDP $=2\mathrm{.}9$ million E$80$s and subgrade design is SG$3.$ Show your work on the design tables and catalogues. Also, draw neat free$-$hand sketches to present the alternative pavement structures including the subgrade layers. The sketch must indicate pavement layers' names, materials, and layer thicknesses.

$(22)$