Traffic and Highway Engineering
5th Edition
ISBN: 9781305156241
Author: Garber, Nicholas J.
Publisher: Cengage Learning
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Chapter 4, Problem 7P
To determine
Whether the engineer can conclude that the average speed of large trucks is the same as for passenger cars.
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Consider only a single lane of a highway. Based on extensive data from an urban freeway it is assumed thatfree-flow speeds (i.e., there are no jams) can best be represented by a Normal distribution with mean andstandard deviation 119 km/h and 13.1 km/h, respectively.1. What is the probability that the speed of a randomly selected vehicle is between 100 and 120 km/h?2. What is the expected number of vehicles between two vehicles that exceed the posted speed limit of100 Km/h?
You can use the Z table for calculating the final answer. You can also write your final answer in form ofR functions or as PDF/CDF of statistical distributions with correct arguments.
Question: A section of highway is known to have a free-flow speed of 55 mph and a
capacity of 3300 veh/hr. In a given hour, 2100 vehicles were counted at a specified
point along this highway section under uncongested conditions. If the linear speed-
density relationship applies, what would you estimate the space-mean speed of these
2100 vehicles to be? Show all the calculation steps.
Question 3:
(a) A section of highway is known to have a free-flow speed of 95 km/h and a capacity of 3300
veh/h. Your summer student indicates that the average time in between passing vehicles was 1.6
seconds during an hour of monitoring.
If the linear speed-density relationship applies, what was the space-mean speed of the vehicles
during the hour of monitoring?
Chapter 4 Solutions
Traffic and Highway Engineering
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