A highway has a posted speed limit of 50mph and, on one section, has both horizontal and vertical curves, as shown in the following Figure. A recent daytime crash (driver traveling and striking a stationary roadway object) resulted in a fatality and a lawsuit alleging that the speed limit is an unsafe speed for the curves. 1) Evaluate if the roadway design (horizontal and vertical curves) is reasonable as compared to the minimum curve length requirement due to sight distance. 2) Based on the above calculations, comment if the roadway design is the cause of this crash. Plane view PC=16+00 Profile view Gl= -2% 24ft Sight obstruction 80⁰ PVC = 14+00 e=8% PT=32+75 G2= + 4% PVT=18+80

A highway has a posted speed limit of 50mph and, on one section, has both horizontal and vertical curves, as shown in the following Figure. A recent daytime crash (driver traveling and striking a stationary roadway object) resulted in a fatality and a lawsuit alleging that the speed limit is an unsafe speed for the curves. 1) Evaluate if the roadway design (horizontal and vertical curves) is reasonable as compared to the minimum curve length requirement due to sight distance. 2) Based on the above calculations, comment if the roadway design is the cause of this crash. Plane view PC=16+00 Profile view Gl= -2% 24ft Sight obstruction 80⁰ PVC = 14+00 e=8% PT=32+75 G2= + 4% PVT=18+80

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter7: Intersection Design

Section: Chapter Questions

Problem 8P

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