Truck Terminal and Corridor Performance Analysis
Freight transportation planning is largely limited by the amount, quality and detail of truck trip data. Most truck movement data is reported at the inter-county level and is represented as aggregated tonnages that must be broken down to truck trips. Additionally, intra-county flows can be largely under-represented and commercially available commodity flow databases such as TRANSEARCH are prohibitively expensive. Surveying truck drivers (such as at truck stops or at terminal gates) and following trucks from terminals is time-consuming and requires a great amount of labor to geocode the trip origins and destinations. Truck trip traffic generated from these aforementioned sources relies on outdated and insufficient traffic generation data and models, shortest path algorithms and spot counts and the results are seldom validated.
The American Transportation Research Institute (ATRI), with the Federal Highway Administration (FHWA) developed the Freight Performance Measures Web-Based (FPMWeb) tool. FPMWeb continually measures operating speeds (using GPS device data) of a large sample of trucks along 25 interstate corridors. While the data available on the web consists mainly of processed average speed information, ATRI agreed to provide 2 months’ worth of raw GPS data to the University of Memphis and VECTOR. The raw data consist of truck GPS positions recorded once every 5-15 minutes with a unique ID number for the truck, a timestamp and speed. The unique ID numbers may be linked together to identify the route(s) taken by a given truck on a given day.
VECTOR researchers provided technical assistance in analyzing the raw ATRI GPS truck data in achieving the following goals:
- Development of GIS-based models to convert the raw data into useful terminal and corridor usage data.
- Provide key indicators of performance for truck parking and rest areas throughout TN.
- GIS-based analysis of Tennessee truck corridors with a particular focus on state line crossings.
- Validate previous work (primarily low bridge clearances) conducted in developing truck-specific alternate routes.
This project has been completed, however, owing to the confidential nature of the data, the report will only be released once approved by ATRI.
Dr. James Dobbins was the principal investigator of this project. The work was supported by the Intermodal Freight Transportation Institute (IFTI) at the University of Memphis.