Issuu on Google+

Research Digest FORWARD ALL REQUESTS TO: The University of Texas at Austin Center for Transportation Research LIBRARY 1616 Guadalupe St. | Suite 4.202 | Austin, Texas 78701 Phones: (512) 232-3126 and (512) 232-3138 Email: ctrlib@austin.utexas.edu In this Issue:

Southwest Region University Transportation Center (SWUTC)

Table of Contents Item 1.

Compendium of Student Papers : 2010 Undergraduate Transportation Engineering Fellows Program (TTI SWUTC/10/476660-00003-3).......................................................................................... 1

Item 2.

Managed Lane Travelers--Do They Pay for Travel as They Claimed They Would? (TTI SWUTC/11/161002-1)................................................................................................................... 1

Item 3.

The Relationship Between Income and Personal Vehicle Fuel Efficiency and Associated Equity Concerns for the Fuel Tax (TTI SWUTC/11/161007-1)............................................................



Item 4.

Designing Fine Aggregate Mixtures to Evaluate Fatigue Crack-Growth in Asphalt Mixture (CTR SWUTC/11/161022-1).................................................................................................................



Item 5.

The Light-Duty-Vehicle Fleet's Evolution : Anticipating PHEV Adoption and Greenhouse Gas Emissions Across the U.S. Fleet (CTR SWUTC/11/161023-1)......................................................



Item 6.

The Effect of Public Transit on Social Opportunities for Ethnic Minority Populations : Case Study of Huston-Tillotson University Students (CTR SWUTC/11/161024-1)......................................



Item 7.

Development of Reliable Pavement Models (CTR SWUTC/11/161025-1)............................................. 

Item 8.

Optimal Infrastructure Maintenance Scheduling Problem Under Budget Uncertainty (CTR SWUTC/11/161028-1).................................................................................................................



Item 9.

U.S. and Texas International Trade and Transportation (CTR SWUTC/11/161121-1).........................

6

Item 10.

International Air Cargo Operations and Gateways : Their Emerging Importance to the State of Texas (CTR SWUTC/11/167261-1)....................................................................................................

6

Item 11.

Impact of Performance Goals on the Needs of Highway Infrastructure Maintenance (CTR SWUTC/11/169208-1)..............................................................................................................



Item 12.

Another Look at the Question of Density and Rail Transit (TSU SWUTC/11/473700/00052-1).......... 

Item 13.

The Potential for Improving Rail International Intermodal Services in Texas and the Southwest Region of the United States (CTR SWUTC/11/473700-00076-1)........................................ 

Item 14.

Creating a Systems Engineering Approach for the Manual on Uniform Traffic Control Devices (TTI SWUTC/11/476660-00009-1).......................................................................................... 

Item 15.

Optimized Deployment of Emissions Reduction Technologies for Large Fleets (TTI SWUTC/11/476660-00022-1)......................................................................................................... 

Item 16.

Hybrid Distribution Trucks : Costs and Benefits (CTR SWUTC/11/476660-00080-1)......................... 

__________________________________________________________________________________________

Research and Technology Implementation Office

October 2011


Research Digest Item 1 Compendium of Student Papers : 2010 Undergraduate Transportation Engineering Fellows Program SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

TTI SWUTC/10/476660-00003-3 • 2011 This report is a compilation of research papers written by students participating in the 2010 Undergraduate Transportation Scholars Program. The 10-week summer program, now in its 20th year, provides undergraduate students in Civil Engineering the opportunity to learn about transportation engineering through participating in sponsored transportation research projects. The program design allows students to interact directly with a Texas A&M University faculty member or Texas Transportation Institute researcher in developing a research proposal, conducting valid research, and documenting the research results through oral presentations and research papers. The papers in this compendium report on the following topics, respectively: 1) estimating carriers/truckers value of time due to congestion; 2) evaluating retroreflectivity measurement techniques for profiled and rumble stripe pavement markings; 3) analyzing retroreflectivity and color degradation in sign sheeting; 4) evaluating the effectiveness of LED enhanced stop paddles for school crossing guard use; 5) incorporating freight value into the Urban Mobility Report; 6) evaluating ASTM Standard Test Method E2177, retroreflectivity of pavement markings in a condition of wetness; 7) calibrating pavement performance prediction models; and 8) evaluating the effects of concrete curing compounds on hydration. Full-text of this report is available for free download (4.3 MB) from: http://swutc.tamu.edu/publications/technicalreports/compendiums/476660-00003-3.pdf

Item 2 Managed Lane Travelers--Do They Pay for Travel as They Claimed They Would? SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

TTI SWUTC/11/161002-1 • 2011 This study examined if travelers are paying for travel on managed lanes (MLs) as they indicated that they would in a 2008 survey. To achieve the objectives, an Internet-based stated preference (SP) survey of Houston’s Katy Freeway travelers was conducted in 2010. Three survey design methodologies—Db-efficient, random level generation, and adaptive random—were tested in this survey. Separate mixed logit models were developed from the responses obtained from the three different design strategies in the 2010 survey. The implied mean value of travel time savings (VTTS) varied across the design-specific models. Only the Db-efficient design was able to estimate a value of reliability (VOR). Based on this and several other metrics, the Db-efficient design outperformed the other designs. A mixed logit model including all the responses from all three designs was also developed; the implied mean VTTS was estimated as 65 percent ($22/hr) of the mean hourly wage rate, and the implied mean VOR was estimated as 108 percent ($37/hr) of the mean hourly wage rate. Data on actual usage of the MLs were also collected. Based on actual usage, the average VTTS was calculated as $51/hr. However, the $51/hr travelers are paying likely also includes the value travelers place on travel time reliability of the MLs. The total (VTTS+VOR) amount estimated from the all-inclusive model from the survey was $59/hr, which is close to the value estimated from the actual usage. Full-text of this report is available for free download (2.5 MB) from: http://swutc.tamu.edu/publications/technicalreports/161002-1.pdf _______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 1


Research Digest Item 3 The Relationship Between Income and Personal Vehicle Fuel Efficiency and Associated Equity Concerns for the Fuel Tax SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

TTI SWUTC/11/161007-1 • 2011 The fuel tax, which is assessed on the physical amount of fuel purchased by the consumer, is the primary means of funding roadway development at the state and national level. However, because it is assessed on a gallon basis, drivers of vehicles with a low fuel efficiency pay more per mile for use of the roadway than drivers of more fuel efficient vehicles. If there is a relationship between fuel efficiency and income, such that lower income drivers are more likely to drive a low fuel efficiency vehicle, then the equity of the fuel tax is in question. In this study, researchers analyzed over 350,000 vehicle registration records from around the State of Texas to determine if areas with a lower median income had a higher distribution of low fuel efficiency vehicles. Researchers found that vehicles registered in lower income areas tended to have lower average fuel efficiencies than vehicles registered in areas with mid-range and higher income. Lower income areas and rural areas were also more likely to have a higher percentage of class 35 vehicle registrations, usually larger light duty pickup trucks and sport utility vehicles, which tend to have lower fuel efficiency. Full-text of this report is available for free download (613 KB) from: http://swutc.tamu.edu/publications/technicalreports/161007-1.pdf

Item 4 Designing Fine Aggregate Mixtures to Evaluate Fatigue Crack-Growth in Asphalt Mixture SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/161022-1 • 2011 Fatigue cracking is a significant form of pavement distress in flexible pavements. The properties of the sand-asphalt mortars or fine aggregate matrix (FAM) can be used to characterize the evolution of fatigue crack growth and selfhealing in asphalt mixtures. This study compares the internal microstructure of the mortar within a full asphalt mixture to the internal microstructure of the FAM specimen. This study also conducts a limited evaluation of the influence of mixture properties and methods of compaction on the engineering properties of the FAM specimens. The results from this study, although limited in number, indicate that in most cases the SGC compacted FAM specimen had a microstructure that most closely resembled the microstructure of the mortar within a full asphalt mixture. Another finding from this study was that, at a given level of damage, the healing characteristic of the three different types of FAM mixes was not significantly different. This indicates that the healing rate is mostly dictated by the type of binder and not significantly influenced by the gradation or binder content, as long as the volumetric distribution of the mastic was the same. In other words, the inherent healing characteristics of the asphalt binder plays a more significant role relative to other properties (e.g. volumetrics) in the overall fatigue cracking resistance of the asphalt mixture. Full-text of this report is available for free download (4 MB) from: http://swutc.tamu.edu/publications/technicalreports/161022-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 2


Research Digest Item 5 The Light-Duty-Vehicle Fleet's Evolution : Anticipating PHEV Adoption and Greenhouse Gas Emissions Across the U.S. Fleet SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/161023-1 • 2011 The first part of this report relies on stated and revealed preference survey results across a sample of U.S. households to first ascertain vehicle acquisition, disposal, and use patterns, and then simulate these for a synthetic population over time. Results include predictions of future U.S. household-fleet composition, use, and greenhouse gas (GHG) emissions under nine different scenarios, including variations in fuel and plug-in-electric-vehicle (PHEV) prices, newvehicle feebate policies, and land-use-density settings. This work highlights the impacts of various directions consumers may head with such vehicles. For example, twenty-five-year simulations at gas prices at $7 per gallon resulted in the second highest market share predictions (16.30%) for PHEVs, HEVs, and Smart Cars (combined) — and the greatest GHG-emissions reductions. The stricter feebate policy (pivot point at 30 mpg and fee or rebate rate of $400 per mpg) – coupled with gasoline at $5 per gallon – resulted in the highest market share (16.37%) for PHEVs, HEVs, and Smart Cars, but not as much GHG emissions reduction as the $7 gas price scenario. Excepting the low PHEV price and two feebate policy simulations, all other scenarios predicted a lower fleet VMT. While plug-in vehicles are now hitting the market, their adoption and widespread use will depend on thoughtful marketing, competitive pricing, government incentives, reliable driving-range reports, and adequate charging infrastructure. The second part of this report relies on data from the U.S. Consumer Expenditure Survey (CEX) to estimate the welfare impacts of carbon taxes and household-level capping of emissions (with carbon-credit trading allowed). A translog utility framework was calibrated and then used to anticipate household expenditures across nine consumer goods categories, including vehicle usage and vehicle expenses. An input-output model was used to estimate the impact of carbon pricing on goods prices, and a vehicle choice model determined vehicle type preferences, along with each household’s effective travel costs. Behaviors were predicted under two carbon tax scenarios ($50 per ton and $100 per ton of CO2-equivalents) and four cap-and-trade scenarios (10-ton and 15-ton cap per person per year with trading allowed at $50 per ton and $100 per ton carbon price). Carbon taxes were found to relatively regressive than a cap-and-trade setting (in terms of taxes paid per dollar of expenditure), but a tax-revenue redistribution can be used to offset this regressivity. In the absence of substitution opportunities (within each of the nine expenditure categories), these results represent highly conservative (worst-case) results, but they illuminate the behavioral response trends while providing a rigorous framework for future work. Full-text of this report is available for free download (1.4 MB) from: http://swutc.tamu.edu/publications/technicalreports/161023-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 3


Research Digest Item 6 The Effect of Public Transit on Social Opportunities for Ethnic Minority Populations : Case Study of HustonTillotson University Students SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/161024-1 • 2011 Travel time to destinations in the Austin area continues to rise during both peak and off-peak hours. With increased congestion and higher gas prices, some individuals are traveling more selectively and viewing public transit as a costsaving alternative to the automobile. However, a substantial number of Austinites remain solely dependent on their automobiles for transportation. This study analyzes the travel patterns of students attending Huston-Tillotson University (HT), an Historical Black College and University (HBCU). This population does not utilize public transit, and is mostly car dependent. Reasons given include the need to be independent, the inefficiency of Capital Metropolitan Transportation Authority bus (travel time and routes), condition of bus stops, and the fear of crime while waiting for a bus. During the Spring of 2009, focus groups were held on HT’s campus, and surveys were distributed to the broader student body. From September 2009 – May 2010, an environmental analysis of the built environment surrounding 38 bus stops in three locations was performed using an established survey tool. The researchers determined that both studies were necessary to test whether an environmental analysis would support the findings of the focus groups and student surveys. Using GIS, a cluster analysis of bus stop environments, and cumulative distribution functions to explore bus travel time to reported destinations, the researchers found that the students’ perceptions were not always consistent with the environmental analysis. The cluster analysis revealed spatial differences when identifying negative attributes. However, none of the bus stop structures in the three areas were in very poor condition. The researchers suggest that a transit training program for HT students would be beneficial in improving ridership. Full-text of this report is available for free download (8.9 MB) from: http://swutc.tamu.edu/publications/technicalreports/161024-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 4


Research Digest Item 7 Development of Reliable Pavement Models SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/161025-1 • 2011 The current report proposes a framework for estimating the reliability of a given pavement structure as analyzed by the Mechanistic-Empirical Pavement Design Guide (MEPDG). The methodology proposes using a previously fit response surface, in place of the time-demanding implicit limit state functions used within the MEPDG, in combination with an analytical approach to estimating reliability using First-Order and Second-Order Reliability Methods (FORM and SORM). Additionally, in order to assess the accuracy of the FORM and SORM reliability estimates, Monte Carlo simulations are also performed. A case study based on a three-layered pavement structure is used to demonstrate the methodology. Several pavement design variables are treated as random; these include HMA and base layer thicknesses, base and subgrade modulus, and HMA layer binder and air void content. Information on the variability and correlation between these variables are obtained from the Long-Term Pavement Performance (LTPP) program. Response surfaces for limit states dealing with HMA rutting failure are fit using several runs of the MEPDG based on a factorial design of combinations among the aforementioned random variables, as well as traffic, structural, and climatic considerations. These response surfaces are then used to analyze the reliability of the given pavement structure. Using the second moment and simulation techniques, it was found that on average the reliability estimate by the MEPDG is very conservative. Additionally, the validity of the methodology is verified by means of direct simulation using the MEPDG. Finally, recommendations on fitting the response surface are provided to ensure the applicability of the methodology. Full-text of this report is available for free download (4.6 MB) from: http://swutc.tamu.edu/publications/technicalreports/161025-1.pdf

Item 8 Optimal Infrastructure Maintenance Scheduling Problem Under Budget Uncertainty SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/161028-1 • 2011 This research addresses a general class of infrastructure asset management problems. Infrastructure agencies usually face budget uncertainties that will eventually lead to suboptimal planning if maintenance decisions are made without taking the uncertainty into consideration. It is important for decision makers to adopt maintenance scheduling policies that take future budget uncertainty into consideration. The author proposes a multistage, stochastic linear programming model to address this problem. The author also develops solution procedures using the augmented Lagrangian decomposition algorithm and scenario reduction method. A case study exploring the computational characteristics of the proposed methods is conducted and the benefit of using the stochastic programming approach is discussed. Full-text of this report is available for free download (509 KB) from: http://swutc.tamu.edu/publications/technicalreports/161028-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 5


Research Digest Item 9 U.S. and Texas International Trade and Transportation SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/161121-1 • 2011 This report examines various aspects of international trade, transportation, and foreign practices implemented facilitate and fund transport-related infrastructure. The report is composed of six chapters. The first chapter provides an overview of the U.S. international trade outlook. The second chapter describes the roles played by air cargo transport, ports and ocean carriers, railroads, and the motor carrier industry in U.S. international trade. The third and fourth chapters focus on Texas-specific international trade and modal gateways. The fifth chapter reviews various transport funding mechanisms, Intelligent Transportation System (ITS) applications, and forms of public-private partnerships adopted in various foreign countries. The final chapter describes the expansion of the Panama Canal and its likely Texas impacts. Full-text of this report is available for free download (6 MB) from: http://swutc.tamu.edu/publications/technicalreports/161121-1.pdf

Item 10 International Air Cargo Operations and Gateways : Their Emerging Importance to the State of Texas SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/167261-1 • 2011 Air cargo transport has become particularly important in today’s expanding global economy for the movement of high-value goods such as electronics, computer components, precision equipment, medical supplies, auto parts, and perishables. Air cargo operations allow fast, frequent, and predictable transit as an increasing number of companies out-source manufacturing to remote locations of the world. Decreasing product cycles for high-value, hightechnology goods have made fast delivery to markets essential. In addition, local industries have become global traders, who can reach consumers worldwide. This report examines the potential of Texas-based airports, especially Dallas-Ft. Worth International Airport and the Houston Airport System, to emerge as international gateways for global trade in general and trans-Pacific trade in particular. The period covered is 2001 to 2006. The report is composed of four chapters. The first chapter examines global, U.S., and Texas air cargo trends. The second chapter addresses air freight performance and activities at Texas airports. The third chapter discusses the relationship between air cargo/passenger operations and their impacts on local economic development. The final chapter discusses the policy implications for the State of Texas. Full-text of this report is available for free download (561 KB) from: http://swutc.tamu.edu/publications/technicalreports/167261-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 6


Research Digest Item 11 Impact of Performance Goals on the Needs of Highway Infrastructure Maintenance SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/169208-1 • 2011 Although it is widely accepted that establishing suitable performance goals is critical for system maintenance and preservation, a framework that considers the inter-relationship between conflicting objectives of minimum maintenance and rehabilitation costs, deferred maintenance costs, and vehicle operating costs to the users does not exist. This report proposes a methodological framework that is aimed at assisting highway agencies with the problem of objectively analyzing policy decisions in terms of the performance goals for their highway networks that would minimize the total transport costs to the society. In a case study of the proposed framework, the highway network managed by the Texas Department of Transportation was examined for different performance goals. The results from the case study indicate that setting lower performance goals lead to savings in the M&R needs, but at the same time, they also significantly increase the exogenous costs such as deferred maintenance costs and the vehicle operating costs. Full-text of this report is available for free download (364 KB) from: http://swutc.tamu.edu/publications/technicalreports/169208-1.pdf

Item 12 Another Look at the Question of Density and Rail Transit SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

TSU SWUTC/11/473700/00052-1 • 2011 Long community discussions about rail often include whether a city’s spatial distribution of housing, employment and other trip generators is conducive to supporting rail transit. A city’s decision to construct rail transit is based on an array of variables, some of which may indirectly relate to density. Other variables considered important are number of new riders, operating costs and construction costs. Although density is not a direct variable in the list of criteria, numerous studies show a positive correlation with ridership, confirming density as an explanation for the number of riders a system will attract. For that reason, opponents of new rail systems often raise lack of density as reason not to pursue rail. This research compares density in a few select cities with the accepted transit efficiency performance measure of operating cost per passenger mile to determine whether this statistic is better in more dense cities. Full-text of this report is available for free download (505 KB) from: http://swutc.tamu.edu/publications/technicalreports/473700-00052-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 7


Research Digest Item 13 The Potential for Improving Rail International Intermodal Services in Texas and the Southwest Region of the United States SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/473700-00076-1 • 2011 The report covers a period of great significance for railroading in the U.S. as it contains a number of milestones now shaping the future performance of the industry. The specific subject is improving intermodal service so that it can support state and regional highway planning, now facing severe financial cut-backs as revenue sources become fully committed to bond servicing, user taxes, loose purchasing power and fuel consumption begins to fall. Intermodal traffic grew strongly in the period 1995-2007 and UP and BNSF trans-continental routes were improved largely on the back of intermodal demand. Alliances with larger trucking companies strengthened and transportation officials began to ask whether rail could take some of the predicted freight off key highway corridors. This report addresses elements of this question, more especially as it relates to intermodal traffic in Texas and the Southwest. The report comprises the following sections. Chapter 2 considers the changes in rail freight since the Staggers Act, Chapter 3 evaluates Class 1 intermodal service, and Chapter 4 identifies the major trade corridors serving Texas and the Southern region of the U.S. Chapter 5 describes rail bottlenecks on the state rail system that might impact future intermodal growth, and Chapter 6 concludes by examining the strengths, weaknesses, opportunities and threats to rail intermodal service in Texas and the Southern region over the next decade. Full-text of this report is available for free download (2.3 MB) from: http://swutc.tamu.edu/publications/technicalreports/473700-00076-1.pdf

Item 14 Creating a Systems Engineering Approach for the Manual on Uniform Traffic Control Devices SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

TTI SWUTC/11/476660-00009-1 • 2011 Topic: Process for Selecting or Installing Traffic Control Devices The Manual on Uniform Traffic Control Devices (MUTCD) provides basic principles for use of traffic control devices (TCD). However, most TCDs are not explicitly required, and the decision to use a given TCD in a given situation is typically made by an engineer (or an individual working under engineering supervision) based on a variety of information including, but not limited to, the MUTCD. There are many other factors not addressed by the MUTCD that can lead to differences in the decision-making process. To assist engineers with evaluating these factors, this research developed a decision analysis process to assist engineers with making TCD decisions. The value of this research is the idea that the decision analysis process for TCD can be modeled and analyzed using appropriate factors including need, impacts, influences, and cost. This process will contribute to more uniform decisions amongst all levels of experience in TCD decision-making. When applying this research, it is important to remember that it is not the intent of this process to remove engineering judgment. This is an important part of the process and should remain as such. Full-text of this report is available for free download (1.2 MB) from: http://swutc.tamu.edu/publications/technicalreports/476660-00009-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 8


Research Digest Item 15 Optimized Deployment of Emissions Reduction Technologies for Large Fleets SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

TTI SWUTC/11/476660-00022-1 • 2011 This research study produced an optimization framework for determining the most efficient emission reduction strategies among vehicles and equipment in a large fleet. The Texas Department of Transportation’s (TxDOT’s) fleet data were utilized to identify the key factors as well as refine and demonstrate the developed framework. TxDOT owns and operates more than 11,000 vehicles, of which approximately 3,200 units are non-road diesel equipment. TxDOT is considering serious actions to reduce emissions from its fleet, especially in designated non-attainment (NA) and near non-attainment (NNA) areas. This project includes a comprehensive literature review, identifies the key parameters affecting the deployment of resources to reduce emissions, and develops a framework for producing an optimal emission reduction strategies deployment plan for a typical large fleet. The capabilities of the proposed framework are demonstrated through a set of five case study scenarios. These scenarios cover a range of location preferences, budget limits, and analysis scales. TxDOT’s fleet data were utilized in this effort. The mathematical formulation and optimization modeling is implemented using ILOG CPLEX and Visual C++ platforms. Full-text of this report is available for free download (755 KB) from: http://swutc.tamu.edu/publications/technicalreports/476660-00022-1.pdf

Item 16 Hybrid Distribution Trucks : Costs and Benefits SOUTHWEST REGION UNIVERSITY TRANSPORTATION CENTER (SWUTC)

CTR SWUTC/11/476660-00080-1 • 2011 The respective populations of the United States and Texas are expected to significantly increase over to the next several decades, primarily in urban and metropolitan areas. Economists have also predicted that oil prices will rise in real terms during the same period. Air quality is getting worse in a number of metropolitan areas, triggering nonattainment penalties and spurring an interest in cleaner transportation. Incentives and new policies must be adopted to increase the efficiency of the transportation system and thus move freight with a reduced impact on society and the environment. Hybrids can potentially help solve this issue through their increased fuel economy and reduced emissions. This project evaluated a package delivery truck, beverage delivery truck, and a refuse truck. The research determined that the additional cost (with current prices) of the hybrid refuse truck was justified, but not for the other two trucks. The social cost of emissions was also estimated to help justify hybrids’ implementation. With this information, the rate of hybrid truck adoption was estimated for various policy scenarios. The results indicated that a correctly designed incentive program can greatly increase the rate of hybrid adoption and could be justified by the additional social benefits of emissions reduction. Full-text of this report is available for free download (3.9 MB) from: http://swutc.tamu.edu/publications/technicalreports/476660-00080-1.pdf

_______________________________________________________________________________________________

Research and Technology Implementation Office

October 2011

Page 9


Research Digest, Oct '11 issue, Southwest Region University Transportation Center research reports