Question $2$

It is required to connect two straights $(=50)$ with a composite curve, comprising entry

transition, circular arc and exit transition. The initial design parameters are $V=105k\frac{m}{h},$

$q=0\mathrm{.}6\frac{m}{s^3},=0\mathrm{.}15$ and crossfall $1$ in $14\mathrm{.}5(tan=0\mathrm{.}07).$

a$.$ Calculate the radius of the circular arc $(4$ marks$)$

b$.$ Determine the total length of the curve $(12$ marks$)$

c$.$ Calculate the actual value of superelevation $($in metres$)$ at the intersection of the

transition and the circular curve given the width of road as $10$ m $.(4$ marks$)$

Aide memoir

$S=\frac{L^2}{24}R,q=\frac{V^3}{{3\mathrm{.}6}^3}RL$