A horizontal curve on a two-lane highway (with 7.2 m lanes) has a central angle of 33 degrees and is designed for 60 km/h with a 8% superelevation. First, if the PI is at station 30+ 000, what is the station of the PT and how many feet have to be cleared from the inside lane's lane-shoulder edge to provide adequate stopping sight distance? Second, if the normal component of centripetal force was considered, how much shorter would the radius of the curve be?

A horizontal curve on a two-lane highway (with 7.2 m lanes) has a central angle of 33 degrees and is designed for 60 km/h with a 8% superelevation. First, if the PI is at station 30+ 000, what is the station of the PT and how many feet have to be cleared from the inside lane's lane-shoulder edge to provide adequate stopping sight distance? Second, if the normal component of centripetal force was considered, how much shorter would the radius of the curve be?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter15: Geometric Design Of Highway Facilities

Section: Chapter Questions

Problem 21P

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