Traffic Flow Theory: History and Models
Theoretical description of the characteristics of vehicle movements on roadways
Need for traffic flow models
Trafficflow theories, seek to describe in a precise mathematical way, the interactions among vehicles, dr
Geometric Design: Horizontal Alignment
Specifying the directional transition of the roadway in a horizontal plane considering the cornering capabilities of a variety of vehicles.
Outline
Horizontal Alignment
Concepts Vehicle Cornering Horizontal Curve Des
DESIGN TRAFFIC VOLUMES
How to select a designhourly volume? Problem: Variability in traffic volumes by time of day, day of week, time of year, and type of roadway.
Examples of hourly variation
In t r a c it y R o u t e
1 0 .0 8 .0 6 .0 4 .0
Percent of
ENG 106 Homework #3 (due 29 Jan)
Present Worth
5.20 but calculate NPWs instead of NFWs. (b) Also, which project(s) would you select if they
are independent? If they are mutually exclusive and there is also a Do Nothing alt (with no
cash flow)? If they are
ECI 161
Mid Term Exam 1
1/31/2014
Name: _ ID Number: _
Multiple Choice Questions [15 pt]
Instructions: Circle the correct answer.
1) The power to overcome air resistance is proportional to
ECI 161
Mid Term Exam 2
2/23/2015
Name: _ ID Number: _
Multiple Choice Questions [True or False, 15 pt, 3 pt each]
Instructions: Circle the correct answer.
1)
2)
3)
4)
5)
The average wa
Vertical Curve Design
Crest and Sag Curves and
Examples on Composite Curves
Crest Vertical Curves
SSD
PVI
Line of Sight
PVC
G1
PVT
L
G2
h2
h1
When compute SSD (use Table 3.1)
No need to consider grade (G=0)
due to conservative tr
For SSD < L
For SSD > L
2
Queuing Theory and Flow Analysis
The formation of traffic queues during congested periods is a source of considerable time delay and results in a loss of highway performance.
Outline
Traffic Flow Models
Arrival/departure Patterns Poisson Model
Queuing The
Travel Demand and Traffic Forecasting
ECI 161 Winter 2012
Background
To date, we learned to solve the following two types of traffic problems
Given traffic demand, analyze the transportation system performance for a given system configuration Given traffi
Assignments are due at the beginning of class on Thursday, unless stated otherwise. Homework
must be neat, briefly state the problem and assumptions (if any are required), and show the
solution process to receive credit. Show your work, algebraically, BEF
Determine the torque the engine is producing and the engine speed. Problem 2.7
FE — ER: “I'mmﬂ
at top speed, acceleration = 0; thus, FI3 — ER: 0
5280 .
V := 130— V= 190.66? ﬁfs {given}
3500
MM
calculate aerodynamic resistance
p ;= 0.00205 cD := 0.20
Vehicle Dynamics:
Braking Principle
Critical in the determination of stopping
sight distance, roadway surface design,
and accident avoidance systems
Outline
Principles of Braking
Braking Forces and Distribution
Braking distances
ECI 161 Fall
Safe brakin
Geometric Design:
Introduction + Vertical Curve
Design
Highway geometric design specifies details of
component elements for safe and efficient
operations and environmental aesthetics
Geometric Design: function and
aesthetics
2
Source: http:/www.tfhrc.gov/
TimeSpace Trajectories
A simple tool for traffic analysis
Outline
Concept of timespace vehicle trajectories
Simple trajectories and their equations
Stopping distance and stopping time
Safe following distance
Vehicle trajectories for synchronized tr
Signal Coordination
Objectives
Provide good progression for traffic in
certain directions
Reduce delay, number of stops
Maintain uniform speed, reduce number of
accidents
Offset: A time lag between the start (or end) of green of the same
phase at succe
ECI 161 Transportation
System Operations
A quick overview of course requirements
An overview of transportation systems
Vehicle performance
Transportation: Land, Sea, and
Air
Transportation is a large system that crosses
Air
Sea
Land
Rail
Vehicle
What
Signalized Intersections: Timing & Analysis
Signalized intersections serve as the major routing nodes of a roadway network. Optimized signal timing improves the efficiency of intersection traffic operations.
Popular Traffic Detectors
Acoustic GPS (trackin
Intersection Control and Signalization: Concept and Analysis
Control conflicting traffic and pedestrian movements at grade crossings
Signalized Intersection Analysis
Two approaches:
Deterministic arrivals (Use D/D/1) Probabilistic arrivals (Use empirical
Homework
2.32
,=52mph=
V
LT
2.55
=
52
ds
,
Vitr =D
8
.
It
FYS
76,28
=
415ft
=
I
a
11.4 45
=
,
g
,
=3
2.
ZTYS
'
0.055=5.5%2.33
drinking ;
Before
V
somph
=
,
g
32.2s
=
#
D=
so

'
thr
4=73.33
I
Space
,
uI=
1)
and
End
73.33
JYS
D=
385ft
,

D=

#
,trtr=
TV
Homework
5.12
8=300
.
ph
ts=1,7s
,
P(
want
we
/
trtts )=
he
exp (4*511)=0,2

2
0.2
trtts
2.678

see
tr=
0.978
see
n
AH=cfw_ baton
,IItI
5.14
)=cfw_
Nt
t
MH
)
go
t
15
>
De=Ix
1590+190
N=9ot4H
Hy
qN= 121590 t Ex
cfw_
xt
)=
XK
N=
,
150
DH )
Qlt )
120
NK
ECI 161 Discussion
Week 3
M/D/1, M/M/1 Queue
Aircrafts line up before the runway for taking off at
an average rate of 4 aircrafts per 10 minutes. The
runway can accommodate 5 takeoffs per 10 minutes
on average. Compute the aircraft queue, waiting
time in
ECI 161
Mid Term Exam 2
11/16/2015
Name: _ ID Number: _
Problem 1 [40 pt]
A California freeway has four lanes in each direction and carries a traffic volume of 4000 veh/hour. There is a 1 mile long
section of this freeway that has a 6% upgrade. It is know