Problem #$2$

A two$-$lane highway $($one $12\text{'}$ lane in each direction$)$ horizontal curve needs to be designed for $70$ mph with a $1200\text{'}$ radius curve. How much clearance is needed from the edge of the inner lane?

Stopping sight distance, $SSD=vt+\frac{v^2}{2}$a where $t=2\mathrm{.}5sec,a=11\mathrm{.}2f\frac{t}{se{c}^2\text{\&}v}$ is $f\frac{t}{sec}$

${}_S=\frac{SSD**180}{R_v}Eq.1$

$,M_S=R_v(1-cos(\frac{{}_S}{2}))Eq.2$

$M_S=R_v(1-cos(\frac{SSD**90}{R_v}))Eq.3$

$SSD=\frac{R_v}{90}co{s}^{-1}(\frac{R_v-M_s}{R_v})Eq.4$