A data collection study found a linear speed - density relationship for a highway as follows u/65 +k/120 =1 1-Write down the speed - density ( given ) , flow - density and flow - speed models , and plot their relationships 2-raffic study has shown that the time headways between successive vehicles on this highway are exponentially distributed and that 30% of the headways between vehicles are 4 seconds or greater. Apply the traffic models derived in the question a), compute speeds and densities corresponding to this flow.

A data collection study found a linear speed - density relationship for a highway as follows u/65 +k/120 =1 1-Write down the speed - density ( given ) , flow - density and flow - speed models , and plot their relationships 2-raffic study has shown that the time headways between successive vehicles on this highway are exponentially distributed and that 30% of the headways between vehicles are 4 seconds or greater. Apply the traffic models derived in the question a), compute speeds and densities corresponding to this flow.

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter6: Fundamental Principles Of Traffic Flow

Section: Chapter Questions

Problem 13P

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Q1 (a) 10,000 vehicle speed traffic data were collected during the weekday on route FT050 at Batu Pahat, Johor. Suggest how to quantify and describe the basic characteristic of this data. Then explain how the method you suggested can help others to understand the data. ii. Consider the following data from 11 truck speed data climbing a hilly road. Compute 5 (FIVE) basic statistics of the sample speed as following: Sample mean Median а. b. с. Variance d. Range Standard error of the mean е. Speed (km/h) 25 Truck 1 35 3 55 4 15 40 6. 25 7 55 8. 35 9 45 10 11 20
Linear regression analysis was performed on a set of traffic data using speed and density measurements from a highway segment. The following equation was developed. ?? = 57.5 − 0.457?? Use this equation, as well as the fundamental relationship equations to answer the following questions. What is the free-flow speed for this data? What is the jam density of this data? What is the maximum flow of this highway segment? What is the mean speed at this maximum flow?
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Spot speed study has been carried out on a highway and collected data is shown in the table below. Speed range (kmph) No. of vehicles observed 0-10 10 10-20 13 20-30 15 30-40 12 40-50 16 Determine the design speed for checking the geometric design of the highway.
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Q1 (a) i. 10,000 vehicle speed traffic data were collected during the weekday on route FT050 at Batu Pahat, Johor. Suggest how to quantify and describe the basic characteristic of this data. Then explain how the method you suggested can help others to understand the data. (4 marks) ii. Consider the following data from 11 truck speed data climbing a hilly road. Compute 5 (FIVE) basic statistics of the sample speed as following: Sample mean Median а. b. с. Variance d. Range Standard error of the mean е. Speed (km/h) 25 Truck 1 2 35 3 55 4 15 40 6. 25 7 55 8. 35 9. 45 10 11 20
The speed density relationship for a particular road was found to be u = 42.76-0.22k, where 'u' is the speed in kmph and 'k' is the density of vehicles per km. Find the capacity of the road. Give your comment on the result. Sketch the relationship between density and flow and indicate important traffic flow parameters on it.
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7) In studying of traffic flow at a highway toll booth over a course of 60 minutes, it is determined that the arrival and departure rates are deterministic, but not uniform. The arrival rate is found to vary according to the function A(t) = 1.8+0.25t - 0.00312. The departure rate function is u(t) = 1.4 +0 .1lt. In both of these functions, t is in minutes after the beginning of the observation and (t) and „u(t) are in vehicles per minute. At what time does the maximum queue length occur? a) 49.4 min, b) 2.7 min ,c) 19.4 min, d) 60.0 min
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Question 1 In studying traffic flow at a highway toll booth over a course of 60 minutes, it is determined that the arrival and departure rates are deterministic, but not uniform. The arrival rate is found to vary according to the function of A (t) = 1.8 2 +0.25t -0.0030t. The departure rate function is u(t) =1.4 + 0.11 t. In both of these functions, t is in minutes after the beginning of the observation and X(t) and u(t) are in vehicles per minutes. (i) When will the queue that forms be cleared? (ii) What time does the maximum queue length occur and what will be the corresponding queue length? (iii) Determine the total delay (iv) Estimate the average time delay per vehicle