SPR-821: Develop New Methods to use ODOT Weigh-in-Motion Data for Predicting Freight Flow and/or Commodity Patterns

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Freight and freightage -- Oregon -- Statistics, Transportation -- Oregon -- Statistics, Traffic flow--Oregon--Statistics, Weigh-in-motion systems, Transportation -- Oregon -- Planning


The objective of this research is to evaluate weigh-in-motion (WIM) data for use by Oregon Department of Transportation (ODOT) for short-term and long-term highway investment prioritization and the tools and methods used to conduct freight analysis. This research will recommend methods of using the data to produce information, i.e. dashboards, related to heavy truck patterns, ultimately leading to improved analytical tools and methods based on current and emerging patterns of truck movement. The research will also identify and evaluate other data sources (both public and private) with the potential to enhance the information generated using WIM data, such as truck speed data, automatic traffic recorders and commodity flow data. This study will produce an inventory of potential data sources available to ODOT, identifying the pros and cons associated with each and gaging the usefulness to meet the needs of freight mobility.


Data description - Vehicle Classification Plots

As part of the WIM data quality control analysis for ODOT Class 11 trucks, various visual assessments were made. The visual assessments consisted of generating specific plots for each month in each year of WIM data. The first of these plots consists of vehicle classification, in which ODOT Class 01 should account for the largest proportion.

Data description - Number of Trucks by Hour Plots

The second series of plots consist of the number of trucks per hour. This is to assess if there were any consecutive hours in which no trucks were counted.

Data description - Noon-Midnight Hour Volume Comparison Plots

The third series of plots assesses the noon-hour volumes and midnight-hour volumes, where the noon-hour volumes should always be greater than the midnight-hour volumes.

Data description - Speed Distribution Plots

The fourth set of plots consists of speed distribution, where distributions were used to identify any outlying speed observations.

Data description - Observed Weight Distribution Plots

The fifth series of plots were that of the observed weight distribution, the weight recorded at the WIM station as the truck travels. For these plots, there should be a clear lower and upper peak to differentiate unload and loaded trucks, respectively.

Data description - Steering Axle Weight Distribution Plots

The final set of plots were related to steering axle weight and their distributions. For these plots, there should be a clear peak in the distribution at around 10,000 pounds.



Vehicle Classification Plots.pdf (4765 kB)
Vehicle Classification Plots

Number of Trucks by Hour Plots.pdf (9231 kB)
Number of Trucks by Hour Plotsd

Noon-Midnight Hour Volume Comparison Plots.pdf (3577 kB)
Noon-Midnight Hour Volume Comparison Plots

Speed Distribution Plots.pdf (4388 kB)
Speed Distribution Plots

Observed Weight Distribution Plots.pdf (4978 kB)
Observed Weight Distribution Plots

Steering Axle Weight Distribution Plots.pdf (5152 kB)
Steering Axle Weight Distribution Plots