EVALUATING SPEED DIFFERENCES BETWEEN PASSENGER VEHICLES and HEAVY TRUCKS for TRANSPORTATION- RELATED EMISSION MODELING Shauna L
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View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Digital Repository @ Iowa State University InTrans Project Reports Institute for Transportation 7-2004 EVALUATING SPEED DIFFERENCES BETWEEN PASSENGER VEHICLES AND HEAVY TRUCKS FOR TRANSPORTATION- RELATED EMISSION MODELING Shauna L. Hallmark Iowa State University, [email protected] Hillary Isebrands Iowa State University, [email protected] Follow this and additional works at: http://lib.dr.iastate.edu/intrans_reports Part of the Civil Engineering Commons Recommended Citation Hallmark, Shauna L. and Isebrands, Hillary, "EVALUATING SPEED DIFFERENCES BETWEEN PASSENGER VEHICLES AND HEAVY TRUCKS FOR TRANSPORTATION-RELATED EMISSION MODELING" (2004). InTrans Project Reports. 148. http://lib.dr.iastate.edu/intrans_reports/148 This Report is brought to you for free and open access by the Institute for Transportation at Iowa State University Digital Repository. It has been accepted for inclusion in InTrans Project Reports by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. EVALUATING SPEED DIFFERENCES BETWEEN PASSENGER VEHICLES AND HEAVY TRUCKS FOR TRANSPORTATION- RELATED EMISSION MODELING Abstract Heavy vehicles emit emissions at different rates than passenger vehicles. They am y behave differently on the road as well, yet they are often treated similarly to passenger vehicles in emissions modeling. Although not frequently considered in calculating emission rates, differences in the operating speeds of passenger vehicles and heavy trucks may influence emissions. The ainm goal of this research project was to evaluate whether heavy trucks typically travel at significantly different operating speeds than passenger vehicles and what impact differences in on-road speeds would have on emissions. Average speeds and spot speeds were collected for heavy trucks and passenger vehicles for four arterial segments and spot speeds were collected for two freeway segments in Des Moines, Iowa. Average and spot speeds were collected for four arterial segments and three freeway segments in the Minneapolis/St. Paul, Minnesota metropolitan area. The er sults of this research show that heavy trucks and passenger vehicles operate differently on the road. Average and spot speeds were compared for heavy trucks and passenger vehicles by facility. Average and spot speeds for heavy-duty trucks were lower than for passenger vehicles for all locations. Differences could have consequences for project level and regional emissions modeling particularly since the ability to demonstrate conformity is based on the ability to correctly estimate and model vehicle activity. Keywords Arterial highways; Average travel speed; Exhaust gases; Freeways; Heavy duty trucks; Mathematical models; Operating speed; Passenger vehicles; Spot speed Disciplines Civil Engineering This report is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/intrans_reports/148 EVALUATING SPEED DIFFERENCES BETWEEN PASSENGER VEHICLES AND HEAVY TRUCKS FOR TRANSPORTATION-RELATED EMISSIONS MODELING DTFH61-03-P-00336 Sponsored by the Transportation Environmental Research Program, Federal Highway Administration Department of Civil, Construction and Environmental Engineering Final Report July 2004 The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. This document is disseminated under the sponsorship of the Federal Highway Administration, U.S. Department of Transportation, in the interest of information exchange. The U.S. Government assumes no liability for the contents or use thereof. CTRE’s mission is to develop and implement innovative methods, materials, and technologies for improving transportation efficiency, safety, and reliability while improving the learning environment of students, faculty, and staff in transportation-related fields. Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. DTFH61-03-P-00336 4. Title and Subtitle 5. Report Date Evaluating Speed Differences Between Passenger Vehicles and Heavy Trucks for July 2004 Transportation-Related Emissions Modeling 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Shauna L. Hallmark, Hillary Isebrands 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Center for Transportation Research and Education Iowa State University 11. Contract or Grant No. 2901 South Loop Drive, Suite 3100 Ames, IA 50010-8634 12. Sponsoring Organization Name and Address 13. Type of Report and Period Covered Federal Highway Administration Final Report U.S. Department of Transportation 14. Sponsoring Agency Code Washington, DC 20590 15. Supplementary Notes This report is available in color at www.ctre.iastate.edu. 16. Abstract Heavy vehicles emit emissions at different rates than passenger vehicles. They may behave differently on the road as well, yet they are often treated similarly to passenger vehicles in emissions modeling. Although not frequently considered in calculating emission rates, differences in the operating speeds of passenger vehicles and heavy trucks may influence emissions. The main goal of this research project was to evaluate whether heavy trucks typically travel at significantly different operating speeds than passenger vehicles and what impact differences in on-road speeds would have on emissions. Average speeds and spot speeds were collected for heavy trucks and passenger vehicles for four arterial segments and spot speeds were collected for two freeway segments in Des Moines, Iowa. Average and spot speeds were collected for four arterial segments and three freeway segments in the Minneapolis/St. Paul, Minnesota metropolitan area. The results of this research show that heavy trucks and passenger vehicles operate differently on the road. Average and spot speeds were compared for heavy trucks and passenger vehicles by facility. Average and spot speeds for heavy-duty trucks were lower than for passenger vehicles for all locations. Differences could have consequences for project level and regional emissions modeling particularly since the ability to demonstrate conformity is based on the ability to correctly estimate and model vehicle activity. 17. Key Words 18. Distribution Statement average speeds—emissions—heavy-duty trucks—passenger vehicles—speed No restrictions. differences 19. Security Classification (of this 20. Security Classification (of this 21. No. of Pages 22. Price report) page) Unclassified. Unclassified. 43 NA EVALUATING SPEED DIFFERENCES BETWEEN PASSENGER VEHICLES AND HEAVY TRUCKS FOR TRANSPORTATION- RELATED EMISSIONS MODELING DTFH61-03-P-00336 Principal Investigator Shauna L. Hallmark, Ph.D. Assistant Professor, Department of Civil, Construction and Environmental Engineering Iowa State University Research Assistant Hillary Isebrands, P.E. This project was funded by the Federal Highway Administration. Center for Transportation Research and Education Iowa State University 2901 South Loop Drive, Suite 3100 Ames, Iowa 50010-8632 Telephone: 515-294-8103 Fax: 515-294-0467 www.ctre.iastate.edu Final Report • July 2004 TABLE OF CONTENTS ACKNOWLEDGEMENTS.........................................................................................................VII EXECUTIVE SUMMARY .......................................................................................................... IX 1. INTRODUCTION ......................................................................................................................1 1.1 Background ......................................................................................................................1 1.2 Project Objectives ............................................................................................................2 2. DATA COLLECTION ...............................................................................................................3 2.1 Site Selection....................................................................................................................3 2.2 Data Collection.................................................................................................................4 2.3 Average Speed Study Methodology...............................................................................10 2.4 Spot Speed Study Methodology.....................................................................................11 2.5 Volume and Vehicle Classification Counts ...................................................................11 3. ANALYSIS AND RESULTS...................................................................................................12 3.1 Average Speed Studies...................................................................................................12 3.2 Spot Speed Studies.........................................................................................................16 3.3 Volume and Vehicle Classification................................................................................19 4. EMISSIONS ANALYSIS.........................................................................................................20 4.1 Sensitivity Analysis........................................................................................................20 4.2 Comparison of Emission Differences for Several Test Locations .................................21