Estimating Link Travel Time on I-70 Corridor

Estimating Link Travel Time on I-70 Corridor
Author: Sarosh I. Khan
Publisher:
Total Pages: 148
Release: 2000
Genre: Travel time (Traffic engineering)
ISBN:

This report represents the findings of a study that demonstrates the feasibility of estimating link travel time and speed in real-time for rural, mountainous sections of interstate freeway in Colorado using vehicles instrumented with global positioning system (GPS) receivers, serving as probes in traffic streams. The system configuration developed includes a cost-effective, portable GPS deployment unit, communication links to a server PC and an integrated prototype system for vehicle tracking and estimating link travel time statistics. This study was carried out in two phases. The objective of the first phase was to identify a cost-effective means of monitoring traffic within a rural, mountainous stretch of the I-70 freeway. An algorithm was developed to estimate average link speed, travel time and the standard error of estimates to provide user information on the reliability of the estimates based on the probe data. The algorithm was tested for different traffic conditions and geometric characteristics of links. In the second phase of the project, a real-time demonstrational prototype was developed to receive, process and estimate link travel time and speed statistics in real-time. The system was tested off-line and on-line based on field data received from the I-70 corridor. In addition, GPS receivers were deployed using a commercial vanpool service and the system was evaluated further.

Performance Evaluation of Various Corrosion Protection Systems of Bridges in Colorado

Performance Evaluation of Various Corrosion Protection Systems of Bridges in Colorado
Author: Yunping Xi
Publisher:
Total Pages: 166
Release: 2004
Genre: Concrete bridges
ISBN:

Corrosion of reinforced concrete structures has been a significant problem for many state and transportation agencies since the application of deicing salts was introduced. Much research has been conducted to develop corrosion protection systems that can prolong the life span of reinforced concrete structures. The Colorado Department of Transportation (CDOT) has several routine and experimental measures to prevent corrosion of the rebar including epoxy-coated rebar, calcium nitrite admixture, organic corrosion inhibitors, a thick cover of quality concrete, and a waterproofing membrane covered by an asphalt overlay. An extensive literature review was performed to collect information on various corrosion protection systems that have been used in the U.S. and around the world. Current CDOT practices in terms of corrosion protection measures were reviewed. A draft inspection plan for Colorado's bridge structures was proposed.

Traffic Data Collection and its Standardization

Traffic Data Collection and its Standardization
Author: Jaume Barceló
Publisher: Springer Science & Business Media
Total Pages: 202
Release: 2010-07-20
Genre: Business & Economics
ISBN: 1441960708

A nice night of October 2007, in Beijing, during the XV World Conference on ITS a number of colleagues met informally for a dinner party that spontaneously became a vivid discussion on the importance of traffic data for all types of p- poses. Researchers can hardly do any progress in modeling, developing, and te- ing theories without suitable data, and what practitioners can do in real life is limited not only by technology but also by the availability of the required data. Quite frequently, the data and not the technologies are what determine how far we can go. Any discussion about traffic data leads in a natural way to a discussion on the variety of traffic data sources, formats, levels of aggregation, accuracies, and so on. Consequently, we moved to talk on the initiative that Kuwahara had undertaken in his traffic laboratory at the University of Tokyo, known as the International Traffic Data Base, and thus smoothly but inexorably we came to agree that it would be convenient to organize a workshop to continue our discussion at a more formal level, share our points of view with other colleagues, listen what they had to say and, if possible, d- seminate the findings in our professional and academic communities.

Review of the Public-Private Initiatives Program of the Colorado Department of Transportation

Review of the Public-Private Initiatives Program of the Colorado Department of Transportation
Author: Porter K. Wheeler
Publisher:
Total Pages: 130
Release: 2000
Genre: Public-private sector cooperation
ISBN:

This report assesses the current Public-Private Initiatives (PPI) program from the perspective of all participants and incorporates best practices from other states. Section 2 summarizes innovative finance. The current PPI program and processes are reviewed in section 3. In section 4 the best practices of selected PPI programs in other states and jurisdictions are examined. In section 5 the recommendations for the Colorado Department of Transportation's considerations are presented in the key areas of policy/legal, process, and management.

In-place Voids Monitoring of Hot Mix Asphalt Pavements

In-place Voids Monitoring of Hot Mix Asphalt Pavements
Author: Donna S. Harmelink
Publisher:
Total Pages: 136
Release: 2002
Genre: Pavements, Asphalt
ISBN:

In 1995, the Colorado Department of Transportation implemented the Superpave gyratory mix design to select the optimum asphalt content of a mixture. The optimum asphalt content was not the same as what the department had historically used. The purpose of this study was to gather data to validate the number of gyrations that should be used with the Superpave mix design. Based on the data gathered from the 25 evaluation sections, the optimal number of design gyrations for the Field Mixed/Lab Compacted material is too high. Mixes appear to be too stiff for the traffic and environmental conditions.

Stone Mastic Asphalt in Colorado

Stone Mastic Asphalt in Colorado
Author: Donna S. Harmelink
Publisher:
Total Pages: 120
Release: 2001
Genre: Pavements
ISBN:

This report documents the construction and performance of the Colorado Department of Transportation's (CDOT's) first two Stone Mastic Asphalt (SMA) projects. The first project, located on SH 119 from SH 52 to Longmont, contained three SMA mixes, two polymer-stabilized mixes and one fiber mix. This project successfully demonstrated the design, production and placement of SMA. The second project located on the Colfax Viaduct in Denver was CDOT's first attempt to use SMA on a bridge deck. This project used a polymer-stabilized mix. This project successfully demonstrated the placement of SMA on a bridge deck. SMA is currently being used as a wearing surface in Colorado. Guidelines and a best practice guide have been developed and have been adopted for statewide use. In addition, CDOT's Bridge Branch has developed a specification for using SMA as part of the overlay system.