Question $3$

$3\mathrm{.}1$ Explain the difference between the two main types of road pavement failure. $(3)$

$3\mathrm{.}2$ Briefly explain how the TRH$4$ method integrates the effect of weather condition on pavement structure design.

$3\mathrm{.}3$ Write a short discussion on inverted pavement structure.

$3\mathrm{.}4$ Given: road category B$,$ falls under a dry region, design CBR $=14\%,$ and cumulative traffic per design lane over $20$ years SDP $=3\mathrm{.}9$ million E$80$s$.$

$3\mathrm{.}4\mathrm{.}1$ Use TRH$4$ method to provide all possible alternative pavement structures. Show your work on the design catalogues. Also check your designs against Table $19.$

$3\mathrm{.}45\mathrm{.}2$ Draw neat free$-$hand sketches to present the alternative pavement structures including the subgrade. The sketch must indicate pavement layers' names, materials, and layer thicknesses.

$[40$ marks$]$