Transcript Distribution of Trips- Shopping

Manual Distribution
Trip Distribution/Assignment


Analyzing where trips come from and go to in
relation to development
Results in a determination of traffic that will
use each access point and route on the
roadway network




Total traffic
Development traffic
Non-development (background) traffic
Manual methods: most analysis estimate
distribution and assignment at the
same time
You Start With Major Directions
6%
12%
40%
15%
17%
10%
Then You Distribute Trips To The Network
6%
12%
15%
40%
17%
10%
Major Directions Decided
From Kimley Horn
Distributions Can Change Over Time
Distributions Can Change Over Time
Trip Attenuation


Assign site traffic according to turn
percentages
Reduce site volumes using attenuation
factors to account for “intervening
opportunities” for the trip to end
Sources For Trip Length Frequency



Travel Characteristics Survey
FSUTMS (DISTRIB.OUT report)
National Personal Transportation Survey
(NPTS)
Trip Attenuation Method
Trip Distribution
and
Assignment
Example
Distribution and Assignment
N
Office
335
57
278
Total
Trips Entering
Trips Exiting
83%
17%
% of Exiting
% of Entering
50%
Professional Judgment
% of External
Trips
Office
17
83%
W
101
Trips Exiting
% of Exiting
Total
84
17%
Trips Entering
% of Entering
17%
670
15%
20%
External Trips
% of External
Trips
% of External
Trips
15%
% of External
Trips
83%
From ITE Trip Gen
17%
% of Entering
% of Exiting
83
100
Trips Exiting
Total
S
17
Trips Entering
% of Entering
83%
% of Exiting
23
Trips Entering
111
Trips Exiting
134
E
Total
Distribution and Assignment
N
Office
278
57
Trips Entering
W
17
Trips Exiting
23
Office
Trips Exiting
Trips Entering
84
111
Trips Entering
Trips Exiting
83
17
Trips Exiting
Trips Entering
S
E
Distribution and Assignment
N
Office
278
57
Trips Entering
W
17
Trips Exiting
23
Office
Trips Exiting
Trips Entering
84
111
Trips Entering
Trips Exiting
83
17
Trips Exiting
Trips Entering
S
E
Distribution and Assignment
N
Office
278
Trips
Exiting
W
Office
S
E
91
N
167
+111
Northbound
Office
167
278
Office
111
87
91
N
980
Northbound
Retail and Apt.
980
Northbound
Office
167
278
Office
111
87
Assignment
564
742
690
566
Assignment
Background
Traffic
Background
Traffic
Northbound
Retail and Apt.
980
980
Total Northbound
Development Traffic
1258
167
Office
111
Northbound
Office
278
91
742
564
SB Link 2 Volume:
564 Background
+ 612 Development
====
1,176 Total
NB Link 2 Volume:
742
Background
+ 780 = 1,258 * 62% Development Traffic
====
1,522 Total
16% 62% 22%
CR
48
16% 62% 22%
1258
Total Northbound
Development Traffic
524
91
690
SB Link 1 Volume:
690 Background
+ 987 Development
=====
1,677 Total
Background
Traffic
NB Link 1 Volume:
524 Background
+ 1258 Development
=====
1,782 Total
742
564
91
Assignment
NB Link 2 Volume:
742
Background
1522 + 780 = 1,258 * 62% Development Traffic
====
1,522 Total
Total Northbound
Traffic Link 2
CR
48
1258
1782
Total Northbound
Development Traffic
524
Total Northbound
Traffic Link 1
690
91
Background
Traffic
NB Link 1 Volume:
524 Background
+ 1258 Development
=====
1,782 Total