Transportation Intelligence

Volume 7 Number 5

October 2009

Pavements

Administration

Traffic Control

Urban

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Traffic Control
Spatiotemporal Effects of Segregating Different Vehicle Classes on Separate Lanes
Spatiotemporal analysis of real freeway traffic reveals that carpool lanes are not as damaging as previously reported. To the contrary, the analysis unveils a surprising benefit of carpool lanes that should be even greater when special lanes are used to segregate very different vehicle classes, such as buses and cars. The paper pursues this finding and shows how reserving lanes on freeways and city streets for bus-use only can favorably affect not just buses, but also cars. (University of California at Berkeley Center for Future Urban Transport Working Paper UCB-ITS-VWP-2008-8, September 2008, 17 p.)

Administration
Toward a Generic Protocol for Infrastructure Life Cycle Cost
The purpose of this report is to provide a synthesis of current state of the practice and state of the art Life Cycle Cost Analysis (LCCA) practices by agencies such as Ministry of Transportation Ontario (MTO), FHWA, and various others. It also examines and analyzes some alternative approaches to LCCA in the generic asset management context with an attempt to minimize the Life Cycle Cost of highway infrastructure. (Ontario Ministry of Transportation Report HIIFP-019, March 2004, 181p.)

Pavements

Field Condition Assessment of Longitudinal Joints in Asphalt Pavements Using Seismic Wave Technologies
Poor-quality longitudinal construction joints often contribute to the poor performance of hot mix asphalt (HMA) pavements. Traditionally, the longitudinal construction joints are evaluated in terms of in-situ density measurements obtained through coring at five different locations across the joint. This approach is destructive, time consuming which limits the implementation of the quality assurance and quality control (QA/QC) plan to ensure the construction of good quality longitudinal joints in asphalt pavements. To address this problem, an innovative non destructive technique (NDT) for condition assessment of the longitudinal construction joints in asphalt pavements has been developed at the University of Waterloo in collaboration with the Ministry of Transportation, Ontario. This method involves the use of ultrasonic surface waves to assess the relative condition of the longitudinal joints in comparison to the condition of the adjacent good quality joint-free asphalt pavement surface. (Ontario Ministry of Transportation Highway Infrastructure Innovation Funding Program Report HIIFP-042, September 21-24, 2008, 22 p.)

Investigating Premature Pavement Failure Due to Moisture
This report details the forensic investigations conducted to identify the causes of pavement failures shortly after a rehabilitation activity on five interstate highway projects in Oregon, and the research efforts conducted to develop guidelines to minimize the risk of premature failures on future projects. One of the principal objectives of this research effort was to identify sources of moisture and other conditions that let to the early rutting problems observed along the five projects. Appendices (46.5 MB PDF) are available at http://www.oregon.gov/ODOT/TD/TP_RES/docs/Reports/2009/Moisture_Damage_Appendices.pdf (Oregon Department of Transportation Report FHWA-OR-RD-10-02, July 2009, 167p.)

Use of Fly Ash for Reconstruction of Bituminous Roads
When reconstructing roads surfaced with hot mix asphalt (HMA), the HMA, underlying base, and a portion of the existing subgrade often are pulverized to form a new base material referred to as recycled pavement material (RPM). Similarly, when an unpaved road with a gravel surface is upgraded to a paved road, the existing road surface gravel (RSG) is blended and compacted to form a new base layer that is overlain with an HMA surface. The purpose of this study was to develop a practical method to design local roadways using stabilized RPM or SRSG as the base layer and Class C fly ash as the stabilizing agent. The design method was developed in the context of the “gravel equivalency” (GE) design methodology employed for local roads in Minnesota. (Minnesota Department of Transportation Report MN/RC 2009-27, August 2009, 32p.)

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Concrete

Influence of Surface Condition and Loading on the Corrosion Behaviour of Stainless Steel Reinforcing Bars
The current Canadian Highway Bridge Code specifies a 75 year service life for all new highway bridges. Such requirements cannot be met with conventional “black” steel reinforcement because of the high use of chloride-containing de-icing salts, and the most suitable alternative is stainless steel. Although the lifetime costs of structures with stainless rebar are predicted to be significantly lower than with any other materials, the initial costs are often considered to be prohibitively high. An additional cost, recommended by the alloy suppliers, is imposed by the removal of the mill scale and associated Cr-depleted layer formed during hot rolling of the bar. This is achieved by blasting the mill scale with stainless steel chips and then pickling in a mixture of nitric and hydrofluoric acids. The main purpose of this investigation was to determine if this blasting and pickling process is necessary for the performance in concrete exposed to chlorides, of three grades of stainless steel. (Ontario Ministry of Transportation Highway Infrastructure Innovation Funding Program Report HIIFP-052, February 2009, 60p.)

Cathodic Protection for Life Extension of Existing Reinforced Concrete Bridge Elements
Cathodic protection is the only technology that can directly stop corrosion in reinforced concrete structures. This report examines the use of cathodic protection by state transportation agencies for controlling corrosion on existing reinforced concrete bridge elements. There are descriptions of different types of systems and case studies of states using these systems. As well, there is analysis of reasons that public agencies may or may not employ cathodic protection. Information was gathered through a literature review and a survey of U.S. state transportation agencies and Canadian provincial transportation agencies, augmented by selected interviews. Appendix A is available online at http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_syn_398AppendixA.pdf (Oregon Department of Transportation Report SPR 345, June 30, 2009, 27 p.)

Demonstration of Concrete Maturity Test Process on TH-694/TH-35E Interchange – Unweave the Weave
A maturity protocol will allow a more precise identification of the time when sufficient strength has been gained such that a pavement can be opened to traffic. This way traffic can be regulated to protect the integrity of the pavement while simultaneously streamlining construction operations by avoiding excessive initial cure periods. The overall goal of this research initiative is to develop maturity strength curves for the majority of the paving mixes used by Mn/DOT and test maturity meter implementation on several projects to observe potential difficulties/successes with their use. As such, Mn/DOT SP 6280-304, the TH-694/TH-35E interchange known as “Unweave the Weave” is one of the first Mn/DOT projects to test the implementation of maturity meters in a field setting. (Minnesota Department of Transportation Report MN/RC 2009-26, August 2009, 56p.)

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Administration

Assessing Knowledge Management
The basic premise of this study is that knowledge is an asset, it has value to both individuals and organizations, and knowledge management should be an integral component of asset management. (Ontario Ministry of Transportation Report HIIFP-020, December 2004, 31p.)

Paving the Way: Recruiting Students into Transportation Careers
The transportation industry faces a growing shortage of professional engineers and planners. One key strategy in solving this problem will be to encourage more civil engineering and urban planning students to specialize in transportation while completing their degrees, so that employers have a larger pool of likely recruits. However, very little is known about how these students choose a specialization. To help fill that gap, this report examines the factors that lead civil engineering undergraduates and urban planning masters students to specialize in transportation, as opposed to other sub-disciplines within the two fields. The primary data collection methods were web-based surveys of 1,852 civil engineering undergraduates and 869 planning masters students. The study results suggest steps the transportation community can take to increase the number of civil engineering and planning students who choose to specialize in transportation. (Mineta Transportation Institute Report 08-03, June 2009, 196p.)

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Traffic Control

Advanced Vehicle Control Systems (AVCS) Supporting Intelligent Transportation Systems
This research is an one-year feasibility study funded by MTO. The objective is to investigate how the vision of individual drivers can be extended beyond his/her physical boundary through the use of inter-vehicle communication technology. The study was organized into two work-packages that took place concurrently, namely (1) investigating inter-vehicle communication (IVC) and (2) modelling of the vehicle dynamics. Through (1) we investigate how the vision of individual driver's driving vision can be extended and develop a wireless communication protocol suitable for use in harsh traffic environment. The outcome of this work is then used in (2) to study how individual driver should respond to the information passed to him/her through the IVC or how his/her driving condition initiates a message that is to be broadcasted to other surrounding drivers through the IVC. (Ontario Ministry of Transportation Report HIIFP-064, May 2009, 100p.)

Detecting Pedestrians
With support from FHWA, researchers are integrating the latest camera technology with traffic control to improve safety at intersections. (Public Roads, September/October 2009.)

Driver/Pedestrian Understanding and Behavior at Marked and Unmarked Crosswalks
This report presents the results of a study examining pedestrian and driver knowledge of right-of-way laws. Input for the study came from a series of focus groups and surveys, in addition to observations of pedestrian and driver behavior at a sample of unsignalized, high volume, three- and four-lane intersections in the San Francisco Bay Area. Focus of the study was to identify potential human factors explanations for the crosswalk dilemma. Results of the study reveal that pedestrians and drivers have significantly different knowledge of right-of-way laws and crossing/yielding behaviors in marked versus unmarked crosswalk. Additionally, the study found that pedestrians and drivers exhibit different behaviors in marked versus unmarked crosswalks on multi-lane, higher volume roads. The study concludes with recommendations and analyses of countermeasures for improving pedestrian crosswalk safety. (California PATH Research Report UCB-ITS-PRR-2008-13, July 2008, 225p.)

Managing Traffic Through Work Zones: Preliminary Findings
The overall objectives of this research are to (1) define safe, efficient, reliable and cost-effective means for managing traffic in highway work zones, and (2) develop guidelines for the use of intelligent transportation system technologies for managing delay, defining variable speed limits, guiding the lane merging process, and automated enforcement. This phase of the study, carried out during the April 2004-March 2005 period, used as a starting point the construction zone queue-end warning system research of the Principal Investigator, funded by the Highway Infrastructure Innovation Funding Program of the Ministry of Transportation, Ontario. (Ontraio Ministry of Transportation Highway Infrastructure Innovation Funding Program Report HIIFP-031, June 2005, 20p.)

Managing Traffic Through Highway Work Zones: Role of ITS
This research investigated the role of intelligent transportation system (ITS) technologies for improving safety of road users as well as workers and for enhancing efficiency of traffic flow in highway work zones. The scope of the project covered methodological innovations and ITS-based concept designs. This research was carried out in a simulation test bed. (Ontario Ministry of Transportation Highway Infrastructure Innovation Funding Program Report HIIFP-044, June 2007, 25p.)

Improving the Safety of Mobile Lane Closures
Although traffic controltechniques for road construction and maintenance vary widely, one of the methods experiencing increased use, because of its ability to increase efficiency and minimize operational impacts, is mobile lane closures. The objective of this report is to synthesize practices employed by transportation agencies during mobile lane closures and to summarize research carried out on different components of mobile lane closure. Appendices A-d are available online at http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rrd_339Appendices.pdf (Transportation Research Board NCHRP Research Results Digest 339, August 2009, 48p.)

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Urban

Driving and the Built Environment: The Effects of Compact Development on Motorized Travel, Energy Use, and CO2 Emissions
This report examines the relationship between land development patterns and vehicle miles traveled (VMT) in the United States to assess whether petroleum use, and by extension greenhouse gas (GHG) emissions, could be reduced by changes in the design of development patterns. The report estimates the contributions that changes in residential and mixed-use development patterns and transit investments could make in reducing VMT by 2030 and 2050, and the impact this could have in meeting future transportation-related GHG reduction goals. (US Transportation Research Board Special Report 298, 2009, 180p.)

Essential Smart Growth Fixes for Urban and Suburban Zoning Codes
The U.S. Environmental Protection Agency’s (EPA) Development, Community, and Environment Division (DCED), also known as the Smart Growth Program, has put together this document to help those communities that may not wish to revise or replace their entire system of codes and ordinances, but nevertheless are looking for “essential fixes” that will help them get the smarter, more environmentally responsible, and sustainable communities they want. (US Environmental Protection Agency Report, September 2009, 52p.)

Metropolitan Planning Organizations: Options Exist to Enhance Transportation Planning Capacity and Federal Oversight
Metropolitan planning organizations (MPO) are responsible for transportation planning in metropolitan areas; however, little is known about what has been achieved by the planning efforts. This congressionally requested report describes (1) the characteristics and responsibilities of MPOs, (2) the challenges that MPOs face in carrying out their responsibilities, (3) how the U.S. Department of Transportation (DOT) provides oversight for MPOs and the extent to which this improves transportation planning, and (4) the options that have been proposed to enhance transportation planning. To address these objectives, GAO surveyed all 381 MPOs (with an 86 percent response rate) and conducted case studies of eight metropolitan areas and conducted a survey of program managers. (US Government Accountability Office Report GAO-09-868, 9 September 2009, 40p.)

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