Problem 2. Consider a freeway section with three lanes in each direction and with a length of 1.25mi (2km) and a +5% grade. In this freeway, the directional peak-hour volume is 3,800 veh/h, from which 76 are trucks and 152 are transit buses. The maximum 15-min volume within the hour of analysis is 1,055 vehicles. The lane widths are 12 ft (3.6m), and shoulder widths are 10 ft (3.1m). There are 2 exit ramps and 1 entrance ramp in the 3 miles in the upstream section and 1 exit ramp and 2 entrance ramp in the 3 miles in the downstream section (consider the same ramp density if using international (km) units). All transit buses will be removed from traffic since the transit service will be replaced by a commuter rail service. However, by removing buses, new additional passage car demand is expected. It is estimated that for each removed bus, 7 new passenger cars will be added to the original traffic volume of 3,800 veh/h. Question: Determine the change in speed and traffic density before and after the bus removal.

Problem 2. Consider a freeway section with three lanes in each direction and with a length of 1.25mi (2km) and a +5% grade. In this freeway, the directional peak-hour volume is 3,800 veh/h, from which 76 are trucks and 152 are transit buses. The maximum 15-min volume within the hour of analysis is 1,055 vehicles. The lane widths are 12 ft (3.6m), and shoulder widths are 10 ft (3.1m). There are 2 exit ramps and 1 entrance ramp in the 3 miles in the upstream section and 1 exit ramp and 2 entrance ramp in the 3 miles in the downstream section (consider the same ramp density if using international (km) units). All transit buses will be removed from traffic since the transit service will be replaced by a commuter rail service. However, by removing buses, new additional passage car demand is expected. It is estimated that for each removed bus, 7 new passenger cars will be added to the original traffic volume of 3,800 veh/h. Question: Determine the change in speed and traffic density before and after the bus removal.

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter9: Capacity And Level Of Service For Highway Segments

Section: Chapter Questions

Problem 8P

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