Page 30 - Lecture Notes DCC3113

Figure 2-4: Origin-destination/direction (OD)

The work involved in the origin-destination studies

i. Defining the study area
ii. Traffic zone
iii. Data collection
iv. Data analysis

b. Volume study

 To collect data on the number of vehicles / pedestrian that pass a point during a specified time
period
 To know whether the existing road can accommodate the vehicles that using a road.
 To ensure the smooth movement of vehicles and traffic safety
 Design for road rehabilitation
 Study the traffic at intersection
 Study of traffic control systems
 Forecast/predict traffic volumes
 Study of traffic accidents
 Analysis of costs - benefits for highway projects

c. Spot speed study

 Conducted to estimate the distribution of speeds of vehicles in a stream of traffic at a particular
location or spot on a highway
 Carried out by recording the speed of a sample of vehicles at specific location
 Will be valid only for the traffic and environmental conditions that exist at the time of study.
 Establish parameter for traffic operation such as speed zones, speed limits, and passing
restriction
 Evaluate the effectiveness of traffic control devices such as variable message sign at work zone.
 Evaluate/determine the adequacy of highway geometric characteristic
 Evaluate the effect of speed on highway and determine speed trends.

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