For the following speed-density relationship of a highway, determine 1) mean free-flow speed, 2) jam density, and 3) capacity from the given data shown in table. The regression model is following Eq.1. Also, assess when this model could be used? k U = U; * e Eq.1 K (vpm) U (mph) 43 38.4 50 33.8 53.2 31 42.3

For the following speed-density relationship of a highway, determine 1) mean free-flow speed, 2) jam density, and 3) capacity from the given data shown in table. The regression model is following Eq.1. Also, assess when this model could be used? k U = U; * e Eq.1 K (vpm) U (mph) 43 38.4 50 33.8 53.2 31 42.3

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 12P

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The table below shows data on speed and corresponding densities on a section of a collector road. It can be assumed that the traffic flow characteristics can be described by the greenberge model, develop an appropriate relationship between flow and density. Also deyerdete the capacity of this section of the road Speed kph density veh/km 60 20 46 32 40.8 38 39.3 40 35.7 45 32.6 50 30.8 53 28.4 57 24.7 65 18.5 80
The optimum speed and the optimum density for the high-speed freeway data set is assumed to be 40 miles per hour and 50 vehicles per mile per lane, respectively. Determine the equations for the Greenberg, Underwood, and Northwestern models, and construct flow-speed-density relationships in a fashion similar to Figure Question 1b.
The data shown below were obtained by time-lapse photography on a highway. Use regression analysis to fit these data to the Greenshields model and determine The mean free speed The jam density The capacity The speed at maximum flow Speed(mi/h) Density (veh/mi) 14.2 85 24.1 70 30.3 55 40.1 41 50.6 20 55 15
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