Traffic flow on a section of a 2 lane road can be described by the Greenshields model with a mean free speed of 80 kph and jam density of 95 veh/km/lane. At the time when a flow was 90% of the capacity of the road, a large dump truck loaded with heavy industrial machinery from an adjacent construction site joins the traffic stream and travels at a speed of 20kph for a length of 6.60 km along the upgrade before turning off onto a dump site. Due to the relatively high flow in the opposite direction, it is impossible for any car to pass the truck. Find how many vehicles will be in the platoon behind the truck by the time the truck leaves the road. Find also the shockwave speed created by the truck.

Traffic flow on a section of a 2 lane road can be described by the Greenshields model with a mean free speed of 80 kph and jam density of 95 veh/km/lane. At the time when a flow was 90% of the capacity of the road, a large dump truck loaded with heavy industrial machinery from an adjacent construction site joins the traffic stream and travels at a speed of 20kph for a length of 6.60 km along the upgrade before turning off onto a dump site. Due to the relatively high flow in the opposite direction, it is impossible for any car to pass the truck. Find how many vehicles will be in the platoon behind the truck by the time the truck leaves the road. Find also the shockwave speed created by the truck.

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 21P

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