This preview shows page 1. Sign up to view the full content.
CIVL 3610  Traffic and Transportation Engineering
ASSIGNMENT 2
Traffic Flow Fundamentals
QUESTION 1
Assuming a linear speeddensity relationship, the mean free speed on a highway
facility lane equals 55 mph near zero density, and the jam density is observed to be
about 200 veh/mi. Assume that the average length of vehicles is 20 ft.
1)
Plot the
q

k

v
curves in proper order.
2)
Write down the speeddensity and flowdensity equations.
3)
Comment on the maximum flow.
4)
Compute speeds and densities corresponding to a flow of 900 veh/hr, describing
traffic conditions from a driver's point of view.
5)
Calculate average headway, gap, clearance, and spacing at maximum flow and
at jam density. Discuss all the results you obtain. Are they realistic?
QUESTION 2
Greenberg has proposed the following speeddensity (
v

k
) model for a traffic stream
on one lane of a highway:
vk
=
30
300
ln(
) (
k
is in vehicles/mile and
v
is in mile/hour).
1)
Sketch the
v

k
relationship clearly and mention the obvious disadvantage of the
model.
This is the end of the preview. Sign up
to
access the rest of the document.
This note was uploaded on 03/15/2012 for the course CIVL 000 taught by Professor Kk during the Spring '10 term at HKUST.
 Spring '10
 KK
 Transportation Engineering

Click to edit the document details