Question: ( 2 5 pts ) Problem 2 . A horizontal curve on a single - lane freeway ramp is 4 0 0 ft long, and

(25pts) Problem 2. A horizontal curve on a single-lane freeway ramp is 400 ft long, and the design speed of the ramp is 45mih. If the superelevation is 10%, the limiting side-friction coefficient is 0.145, and the station of the PC is 17+35, what is the station of the PI and how much distance must be cleared from the center of the lane to provide adequate stopping sight distance (SSD)? SSD design values can be looked up using Table 1.
Table 1. Stopping Sight Distance (AASHTO, A policy on geometric design of highways and streets, Washington D.C.2001)
\table[[us Customary],[Design speed (mph),Brake reaction distance (ft),Braking distance on level (ft,Stopping sight distance],[\table[[Calculated],[(ft)]],\table[[Design],[(ft)]]],[15,55.1,21.6,76.7,80],[20,73.5,38.4,111.9,115],[25,91.9,60.0,151.9,155],[30,110.3,86.4,196.7,200],[35,128.6,117.6,246.2,250],[40,147.0,153.6,300.6,305],[45,165.4,194.4,359.8,360],[50,183.8,240.0,423.8,425],[55,202.1,290.3,492.4,495],[60,220.5,345.5,566.0,570],[65,238.9,405.5,644.4,645],[70,257.3,470.3,727.6,730],[75,275.6,539.9,815.5,820],[80,294.0,614.3,908.3,910]]
Note: Brake reaction distance is based on a time of 2.5 s ; a deceleration rate of 11.2fts2 is used to determine the calculated stopping sight distance.
( 2 5 pts ) Problem 2 . A horizontal curve on a

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