A highway reconstruction project is being undertaken to reduce accident rates. The reconstruction involves a major realignment of the highway such that a 50 mph design speed is attained. At one point on the highway, an 800 ft equal tangent crest vertical curve exists. Measurements show that at 3-52 stations from the PVC, the vertical curve offset is 3 ft. Assess the adequacy of this existing curve in light of the reconstruction design speed of 60 mph and, if the existing curve is inadequate, compute an adequate curve length.

A highway reconstruction project is being undertaken to reduce accident rates. The reconstruction involves a major realignment of the highway such that a 50 mph design speed is attained. At one point on the highway, an 800 ft equal tangent crest vertical curve exists. Measurements show that at 3-52 stations from the PVC, the vertical curve offset is 3 ft. Assess the adequacy of this existing curve in light of the reconstruction design speed of 60 mph and, if the existing curve is inadequate, compute an adequate curve length.

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 19P

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