Civil Engineering Reference
In-Depth Information
10.3 Measuring Mobility
Traveler mobility is de
ned as the distance traveled with a chosen mode within an
acceptable travel time. The time acceptable or budgeted for a trip is related to trip
purpose (e.g., the time acceptable for a work trip is likely to be greater than that for
a shopping trip), and the size of the metro area: for example, in a small urban area
an acceptable trip to work is 20 min long, but in a metro area of over 5 million
people an acceptable trip time to work is 45 min.
The distance traveled is calculated as follows:
Traveler Mobility
¼
Distance Traveled
¼
f
½
¼f½speed of line by haul mode
½
ð
time budgeted for the trip
ð
excess travel time
Þg
þ
Distance from the origin to line
haul vehicle
þ
Distance from line
haul vehicle to trip destination
ð
10
:
2
Þ
Using Eq.
10.2
, traveler mobility provided by each of the four travel modes
shown in Table
10.2
, is plotted in Fig.
10.3
for trip times up to 60 min.
Fig. 10.3 Trip mobility of selected modes and trip time
