Problem Statement: A new rural highway is being designed with a design speed of 60 mph. State guidelines dictate a maximum superelevation rate ($e_{max}$) of 8% (0.08) for areas subject to snow and ice. The maximum safe coefficient of side friction ($f_{max}$) for 60 mph is 0.12.

Calculate the absolute minimum radius ($R_{min}$) allowable for a horizontal curve on this highway.

Problem Statement: A vehicle is traveling at 60 mph ($V$) on a level highway ($G = 0$). The driver's perception-reaction time ($t$) is assumed to be 2.5 seconds, and the deceleration rate ($a$) is 11.2 ft/s². Calculate the required Stopping Sight Distance (SSD).

Given: The formula for SSD in US Customary units is:

Problem Statement: A crest vertical curve connects an ascending grade of +3.0% and a descending grade of -2.0%. The required stopping sight distance ($S$) is 400 ft. Assuming the sight distance is less than the length of the curve ($S \lt L$), and the standard heights of the driver's eye ($h_1 = 3.5 \text{ ft}$) and object ($h_2 = 2.0 \text{ ft}$) apply, calculate the minimum required length of the vertical curve ($L$).

For a crest curve where $S \lt L$, the standard AASHTO formula is: