A road with 4.5% upward grade has a design speed of 90kmph, if coefficient of longitudinal friction 0.36 and driver reaction time was 2.5sec. What will be the sight distance available? Now if this road has approached a crest while meeting another downward grade of 3.6%, determine the length of the vertical curve required when object and driver are located on the same vertical curve. Considering the crest (Point of intersection or PI) RL as 110.00 develop the vertical curve table to 20m interval. Show the RL of key locations as PI or EVC even though these may not fall at regular interval chosen.

A road with 4.5% upward grade has a design speed of 90kmph, if coefficient of longitudinal friction 0.36 and driver reaction time was 2.5sec. What will be the sight distance available? Now if this road has approached a crest while meeting another downward grade of 3.6%, determine the length of the vertical curve required when object and driver are located on the same vertical curve. Considering the crest (Point of intersection or PI) RL as 110.00 develop the vertical curve table to 20m interval. Show the RL of key locations as PI or EVC even though these may not fall at regular interval chosen.

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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