An equal$-$tangent crest curve connects a $+2\mathrm{.}0\%$ and a $-2\mathrm{.}0\%$ grade. The PVC is at station $81+00$

and the PVI is at station $83+75.$ What is the required minimum curve length to allow for

stopping sight distance and passing sight distance for a $45-m\frac{i}{h}$ design speed? Does this curve

accommodate both sight distances?

Table $3\mathrm{.}1$ Stopping Sight Distance

Note: Brake reaction distance is based

on a time of $2\mathrm{.}5s$; a deceleration rate of

$11\mathrm{.}2f\frac{t}{s^2}$ is used to determine calculated

stopping sight distance.

Source: American Association of

State Highway and Transportation

Officials, A Policy on Geometric

Design of Highways and Streets, $6^{th}$

Edition, Washington, DC$,2011.$

Used by permission.