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.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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Concept explainers

Capacity and Level of Service at Intersections

The term capacity is associated with transportation engineering. Capacity helps to understand how many pedestrians or vehicles can be handled by a transport facility. Level of service is also a term associated with transportation engineering. The level of service indicates the performance of the transport facility.

Question

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.

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