Skip to content
Paper

GPS Data Analysis of the Impact of Tolling on Truck Speed and Routing: A Case Study in Seattle, WA

 
Download PDF  (2.51 MB)
Publication: Journal of the Transportation Research Board
Volume: 2411:01:00
Pages: 112-119
Publication Date: 2014
Summary:

Roadway tolls are designed to raise revenue to fund transportation investments and manage travel demand and as such may affect transportation system performance and route choice. Yet, limited research has quantified the impact of tolling on truck speed and route choice because of the lack of truck-specific movement data. Most existing tolling impact studies rely on surveys in which drivers are given several alternative routes and their performance characteristics and asked to estimate route choices. The limitations of such an approach are that the results may not reflect actual truck route choices and the surveys are costly to collect. The research described in this paper used truck GPS data to observe empirical responses to tolling, following the implementation of a toll on the State Route 520 (SR-520) bridge in Seattle, Washington. Truck GPS data were used to evaluate route choice and travel speed along SR-520 and the alternate toll-free Route I-90. It was found that truck travel speed on SR-520 improved after tolling, although travel speed on the alternative toll-free Route I-90 decreased during the peak period. A set of logit models was developed to determine the influential factors in truck routing. The results indicated that travel time, travel time reliability, and toll rate were all influential factors during peak and off-peak periods. The values of truck travel time during various time periods were estimated, and it was found that the values varied with the definition of peak and off-peak periods.

Authors: Dr. Anne Goodchild, Zun Wang
Recommended Citation:
Wang, Zun, and Anne V. Goodchild. “GPS Data Analysis of the Impact of Tolling on Truck Speed and Routing.” Transportation Research Record: Journal of the Transportation Research Board, vol. 2411, no. 1, 2014, pp. 112–119., doi:10.3141/2411-14.
Technical Report

Using Truck Fleet Management GPS Data to Develop the Foundation for a Performance Measures Program

 
Download PDF  (1.12 MB)
Publication: Washington State Transportation Center (TRAC)
Publication Date: 2011
Summary:

Global positioning systems (GPS) used for fleet management by trucking companies provide probe data that can support a truck performance-monitoring program. This paper discusses the steps taken to acquire fleet management data and then process those data so they can eventually be used for a network-based truck performance measures program. While other studies have evaluated truck travel by using GPS, they have used a limited number of project-specific and temporary devices that have collected frequent location reads, permitting a fine-grained performance analysis of specific roadway segments. In contrast, this fleet management GPS data project involved infrequent reads but a relatively large number of different trucks with ongoing data collection. The most effective approach to obtaining the fleet management data was to purchase the data directly from GPS vendors. Because a performance measures program ultimately monitors trips generated by trucks as they travel between origins and destinations, an algorithm was developed to extract trip end information from the data. The large volume of data required automated processing without manual intervention. Because performance measures require travel times and speeds, it was also necessary to evaluate whether speed data from a large number of trucks could compensate for infrequent location reads. Spot speeds recorded by the trucks’ GPS devices were compared to speed data from roadway loops. The researchers concluded that spot speed data can indicate free flow conditions, but sufficient quantities of data are probably necessary to measure congested travel.

 

Authors: Dr. Ed McCormack, Wenjuan Zhao
Recommended Citation:
McCormack, E. D., Zhao, W., & Tabat, D. (2011). GPS truck data performance measures program in Washington State. Washington State Department of Transportation, Office of Research. 
Student Thesis and Dissertations

An Evaluation of Engineering Treatments and Pedestrian and Motorist Behavior on Major Arterials in Washington State

Publication: Washington State Transportation Center (TRAC)
Publication Date: 2008
Summary:

This report examines pedestrian and motorist behavior on arterials in Washington State and determines how, if at all, these behaviors change when various engineering treatments are applied. The treatments that were examined included crosswalk markings, raised medians, in-pavement flashers, signage, stop bars, overhead lighting, and sidewalks. The relationships between pedestrian travel and transit use, origin-destination patterns, traffic signals, and schools were also explored.

The study examined seven locations in the state of Washington. These were State Route (SR) 7 at South 180th Street in Spanaway, SR 99 at South 152nd Street in Shoreline, SR 99 at South 240th Street in Kent, SR 2 between South Lundstrom and King Streets in Airway Heights, SR 2 at Lacrosse Street in Spokane, SR 2 at Rowan Avenue in Spokane, and SR 2 at Wellesley Avenue in Spokane.

Because pedestrian-vehicle collisions are rare when specific locations are studied, other criteria were used to evaluate the conditions and behaviors that were present. These included “conflicts” such as running behavior, motorists having to brake unexpectedly to avoid a pedestrian, pedestrians waiting in the center lane to cross, and more. These unreported, but very common, occurrences enabled the researchers to gain a better understanding of both pedestrian and motorist concerns and behaviors and the effects that improvements might have.

The study concludes that the causes of conflicts are highly varied: ignorance of or noncompliance with the law (by the motorist or the pedestrian), inattention, vehicles following too closely, impatience, anxiety in attempting to catch a bus, use or non-use of pedestrian facilities, placement of features in the built environment, and more. While pedestrian/motorist interaction improves with improved visibility (something which can be obtained through better engineering design and the removal of visual clutter) better education and/or enforcement will also be needed to achieve significant safety benefits.

Authors: Katherine D. Davis, Mark E. Hallenbeck
Recommended Citation:
Katherine D. Davis, Mark E. Hallenbeck. An Evaluation of Engineering Treatments and Pedestrian and Motorist Behavior on Major Arterials in Washington State. Washington State Transportation Center (TRAC), 2008.
Thesis: Array
Paper

ITS Devices Used to Collect Truck Data for Performance Benchmarks

 
Download PDF  (1.61 MB)
Publication: Transportation Research Record
Volume: 1957
Pages: 43-50
Publication Date: 2006
Summary:

This paper documents the development of data collection methodologies that can be used to measure truck movements along specific roadway corridors in Washington State cost-effectively. The intent of this study was to design and test methodologies that could provide information to ascertain the performance of freight mobility roadway improvement projects. The benchmarks created would be used to report on speed and volume improvements that resulted from completed roadway projects. One technology tested consisted of Commercial Vehicle Information System and Networks electronic truck transponders, which were mounted on the windshields of approximately 30,000 trucks traveling in Washington. These transponders were used at weigh stations across the state to improve the efficiency of truck regulatory compliance checks. With transponder reads from sites anywhere in the state being linked through software, the transponder-equipped trucks can become a travel time probe fleet. The second technology tested involved Global Positioning Systems (GPS) placed in volunteer trucks to collect specific truck movement data at 5-s intervals. GPS data made it possible to locate when and where monitored trucks experienced congestion. With this information aggregated over time, it was possible to generate performance statistics related to the reliability of truck trips and even to examine changes in route choice for trips between high-volume origin-destination pairs. The study found that both data collection technologies could be useful; however, the key to either technology is whether enough instrumented vehicles pass over the roadways for which data are required.

Authors: Dr. Ed McCormack, Mark Hallenbeck
Recommended Citation:
McCormack, Edward & Hallenbeck, Mark. (2006). ITS Devices Used to Collect Truck Data for Performance Benchmarks. Transportation Research Record. 1957. 43-50. 10.3141/1957-07. 
Paper

Options for Benchmarking Performance Improvements Achieved from Construction of Freight Mobility Projects

 
Download PDF  (2.95 MB)
Publication: Washington State Transportation Center (TRAC)
Publication Date: 2006
Summary:
This report documents the development of data collection methodologies that can be used to cost effectively measure truck movements along specific roadway corridors selected by transportation agencies in Washington State. The intent of this study was to design and test methodologies that could be used to measure the performance of freight mobility roadway improvement projects against benchmarks, or selected standards, that would be used both as part of the project selection process and to report on speed and volume improvements that resulted from completed freight mobility projects.
One technology tested was Commercial Vehicle Information System and Networks (CVISN) electronic truck transponders, which are mounted on the windshields of approximately 20,000 trucks in Washington. By using software to link the transponder reads from sites anywhere in the state, the transponder-equipped trucks could become a travel-time probe fleet. The second technology tested involved global positioning systems (GPS) placed in volunteer trucks to collect specific truck movement data at 5-second intervals. With GPS data it was possible to understand when and where the monitored trucks experienced congestion and to generate useful performance statistics.
The study found that both data collection technologies could be useful; however, the key to both technologies is whether enough instrumented vehicles pass over the roadways for which data are required. This basic condition affects whether the technologies will be effective at collecting the data required for any given benchmark project. The report also recommends the traffic data that should be collected for a benchmark program and the potential costs of using either data collection technology.

 

 

Authors: Dr. Ed McCormack, Mark Hallenbeck
Recommended Citation:
McCormack, E. D., & Hallenbeck, M. E. (2005). Options for Benchmarking Performance Improvements Achieved from Construction of Freight Mobility Projects. (No. WA-RD 607.1). Washington State Department of Transportation.
Student Thesis and Dissertations

Emissions, Cost, and Customer Service Trade-off Analyses in Pickup and Delivery Systems

Publication Date: 2011
Summary:

As commercial vehicle activity grows, the environmental impacts of these movements have increasing negative effects, particularly in urban areas. The transportation sector is the largest producer of CO2 emissions in the United States, by end-use sector, accounting for 32% of CO2 emissions from fossil fuel combustion in 2008. Medium and heavy-duty trucks account for close to 22% of CO2 emissions within the transportation sector, making systems using these vehicles key contributors to air quality problems. An important well-known type of such systems is the “pickup and delivery” in which a fleet of vehicles pickups and/or delivers goods from customers.

Companies operating fleet of vehicles reduce their cost by efficiently designing the routes their vehicles follow and the schedules at which customers will be visited. This principle especially applies to pickup and delivery systems. Customers are spread out in urban regions or are located in different states which makes it critical to efficiently design the routes and schedules vehicles will follow. So far, a less costly operation has been the main focus of these companies, particularly pickup and delivery systems, and less attention has been paid to understand how cost and emissions relate and how to directly reduce the environmental impacts of their transportation activities. This is the research opportunity that motivates the present study.

While emissions from transportation activities are mostly understood broadly, this research looks carefully at relationships between cost, emissions and service quality at an individual-fleet level. This approach enables evaluation of the impact of a variety of internal changes and external policies based on different time window schemes, exposure to congestion, or impact of CO2 taxation. It this makes it possible to obtain particular and valuable insights from the changes in the relationship between cost, emissions and service quality for different fleet characteristics.

In an effort to apply the above approach to real fleets, two different case studies are approached and presented in this thesis. Each of these cases has significant differences in their fleet composition, customers’ requirements and operational features that provide this research with the opportunity to explore different scenarios.

Three research questions guide this research. They are explained in more detailed below. The present study does not seek to provide a conclusive answer for each of the research questions but does shed light on general insights and relationships for each of the different features presented in the road network, fleet composition, and customer features.

In summary, this research provides a better understanding of the relationships between fleet operating costs, emissions reductions and impacts on customer service. The insights are useful for companies trying to develop effective emission-reduction strategies. Additionally, public agencies can use these results to develop emissions reductions policies.

Authors: Felipe Sandoval
Recommended Citation:
Sandoval, Felipe (2011). Emissions, Cost, and Customer Service Trade-off Analyses in Pickup and Delivery Systems, University of Washington Master's Degree Thesis.
Thesis: Array
Paper

Evaluating Two Low-Cost Methods of Collecting Truck Generation Data Using Grocery Stores

 
Download PDF  (0.20 MB)
Publication: Institute of Transportation Engineers (ITE) Journal
Volume: 81 (6)
Pages: 34–40
Publication Date: 2011
Summary:

Despite their heavy use of the road transportation system, little data is available on trip generation rates for trucks. In this paper, truck trip rates from grocery stores are used in a case study to evaluate and compare two simple methods for collecting data on truck trip generation: telephone interviews and manual counts. The findings from this study showed that grocery stores generated an average of 18 truck trips per day on a typical peak period weekday. The results also showed that a combination of telephone interviews and manual counts was more effective than telephone interviews alone. Information from the telephone interview guided the manual counts and provided a baseline measurement of counts. However, the interviews underreported truck trips when compared to the manual observations.

Authors: Dr. Ed McCormack, Alon Bassok
Recommended Citation:
McCormack, Edward, and Alon Bassok. "Evaluating Two Low-Cost Methods of Collecting Truck Generation Data Using Grocery Stores." Institute of Transportation Engineers. ITE Journal 81, no. 6 (2011): 34.
Paper

GPS Truck Data Performance Measures Program in Washington State

 
Download PDF  (1.12 MB)
Publication: Washington State Transportation Center (TRAC)
Publication Date: 2011
Summary:

The Washington State Department of Transportation (WSDOT), Transportation Northwest at the University of Washington (UW), and the Washington Trucking Associations (WTA) have partnered on a research effort to collect and analyze global positioning systems (GPS) truck data from commercial, invehicle, truck fleet management systems. This effort was funded by the Washington State Legislature, and its purpose is to develop a statewide freight performance measures program for use by WSDOT. This document reviews the program’s previous phases and provides details about the latest phase of the program. The report also provides references to the technical documents that support the program.

Authors: Dr. Ed McCormack, Wenjuan Zhao
Recommended Citation:
McCormack, E. D., Zhao, W., & Tabat, D. (2011). GPS Truck Data Performance Measures Program in Washington State. Washington State Department of Transportation, Office of Research.
Student Thesis and Dissertations

Economic Implications of the Use of Technology in Commercial Vehicle Operations

Publication Date: 2012
Summary:

The effective and efficient movement of freight is essential to the economic well-being of our country but freight transport also adversely impacts our society by contributing to a large number of crashes, including those resulting in injuries and fatalities. Technology has been used increasingly to facilitate safety and operational improvements within commercial vehicle operations, but motor carriers operate on small profit margins, limiting their ability to make large investments without also seeing an economic benefit from such technologies. This dissertation explores the economic implications associated with using onboard monitoring systems to enhance safety in commercial vehicle operations.

First, to better understand how electronic on-board systems work, paper-based methods of recording driver hours of service are compared to automated (or electronically recorded) hours of service for three motor carriers using process analysis. This analysis addressed the differences between manual (paper-based) and electronic methods of recording hours of service, specifically as they relate to the frequencies and magnitude of the errors. Potential errors are categorized by operations within an information-based process and the findings suggest that a reduction of errors can be achieved with an electronic system.

A benefit-cost analysis provides a better understanding of the economic implications of onboard monitoring systems from the perspective of the carrier. In addition to the benefits of reduced crashes, benefits associated with electronic recording of hours of service, reduced mileage, and reduced fuel costs are considered. A sensitivity analysis is used and demonstrates that on-board monitoring systems are economically viable under a wide range of conditions. Results indicate that, for some fleet types, reducing crashes and improving hours of service recording, provides a net benefit of close to $300,000 over the five-year expected lifespan of the system. Furthermore, when exploring additional benefits such as reduced fuel consumption and reduced vehicle miles, benefits can be upwards of seven times more than safety-related benefits. This research also shows that net positive benefits are possible in large and small-sized fleets. Results can be used to inform policies for motivating or mandating carriers to use such systems and to inform carriers regarding the value of system investment.

Authors: Kelly A. Pitera
Recommended Citation:
Pitera, Kelly Ann. "Economic Implications of the Use of Technology in Commercial Vehicle Operations." PhD diss., 2012.
Thesis: Array
Paper

Evaluating the Accuracy of GPS Spot Speeds for Estimating Truck Travel Speed

 
Download PDF  (3.65 MB)
Publication: Transportation Research Record
Volume: 2011
Pages: 101–110
Publication Date: 2011
Summary:

A number of trucking companies use Global Positioning System (GPS) devices for fleet management. Data extracted from these devices can provide valuable traffic information such as spot (instantaneous) speeds and vehicle trajectory. However, the accuracy of GPS spot speeds has not been fully explored, and there is concern about their use for estimating truck travel speed. This concern was addressed by initially comparing GPS spot speeds with speeds estimated from dual-loop detectors. A simple speed estimation method based on GPS spot speeds was devised to estimate link travel speed, and that method was compared with space mean speed estimation based on GPS vehicle location and time data. The analysis demonstrated that aggregated GPS spot speeds generally matched loop detector speeds and captured travel conditions over time and space. Speed estimation based on GPS spot speeds was sufficiently accurate in comparison with space mean speeds, with a mean absolute difference of less than 6%. It is concluded that GPS spot speed data provide an alternative for measuring freight corridor performance and truck travel characteristics.

Authors: Dr. Anne GoodchildDr. Ed McCormack, Wenjuan Zhao
Recommended Citation:
Zhao, Wenjuan, Anne V. Goodchild, and Edward D. McCormack. "Evaluating the accuracy of spot speed data from global positioning systems for estimating truck travel speed." Transportation Research Record 2246, no. 1 (2011): 101-110.