The capacity of a highway is suddenly reduced to 60% of its normal capacity due toclosure of certain lanes in a work zone. If the Greenshields model describes the relationship between speed and density on the highway, the jam density of the highway is112 veh/mi, and the mean free speed is 64.5 mi/h, determine by what percentage thespace mean speed at the vicinity of the work zone will be reduced if the flow upstream is 80% of the capacity of the highway.

The capacity of a highway is suddenly reduced to 60% of its normal capacity due toclosure of certain lanes in a work zone. If the Greenshields model describes the relationship between speed and density on the highway, the jam density of the highway is112 veh/mi, and the mean free speed is 64.5 mi/h, determine by what percentage thespace mean speed at the vicinity of the work zone will be reduced if the flow upstream is 80% of the capacity of the highway.

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 25P

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