Now showing items 1-20 of 42

    • Access Control Design on Highway Interchanges 

      Hesham Rakha; Alejandra Medina Flintsch; Mazen Arafeh; Abdel-Salam Gomaa Abdel-Salam; Dhruv Dua; Abbas, Montasir (Virginia Center for Transportation Innovation and Research, 2008-01-01)
      The adequate spacing and design of access to crossroads in the vicinity of freeway ramps are critical to the safety and traffic operations of both the freeway and the crossroad. The research presented in this report develops ...
    • Asphalt Materials Characterization in Support of Implementation of the Proposed Mechanistic-Empirical Pavement Design Guide 

      Flintsch, Gerardo W.; Loulizi, Amara; Stacey D. Diefenderfer; Khaled A. Galal; Diefenderfer, Brian K. (Virginia Center for Transportation Innovation and Research, 2007-01-01)
      The proposed Mechanistic-Empirical Pavement Design Guide (MEPDG) procedure is an improved methodology for pavement design and evaluation of paving materials. Since this new procedure depends heavily on the characterization ...
    • Assessment of the Durability of Wet Night Visible Pavement Markings: Wet Visibility Project Phase IV 

      Gibbons, Ronald B. (Ronald Bruce); Williams, B. M. (Virginia Center for Transportation Innovation and Research, 2012-06)
      This project encompassed a research effort to establish the durability of pavement markings in an on-road installation. Six marking technologies were installed on a portion of Route 460 in Blacksburg, Virginia. A human ...
    • Automated Vehicle Crash Rate Comparison Using Naturalistic Data 

      Blanco, Myra; Atwood, Jon; Russell, Sheldon; Trimble, Tammy; McClafferty, Julie; Perez, Miguel (Virginia Tech Transportation Institute, 2016-01-08)
      This study assessed driving risk for the United States nationally and for the Google Self-Driving Car project. Driving safety on public roads was examined in three ways. The total crash rates for the Self-Driving Car and ...
    • Composite Pavement Systems: Synthesis of Design and Construction Practices 

      Flintsch, Gerardo W.; Diefenderfer, Brian K.; Orlando Nunez (Virginia Center for Transportation Innovation and Research, 2008-11-01)
      Composite pavement systems have shown the potential for becoming a cost-effective pavement alternative for highways with high and heavy traffic volumes, especially in Europe. This study investigated the design and performance ...
    • Description of the SHRP 2 Naturalistic Database and the Crash, Near-Crash, and Baseline Data Sets 

      Hankey, Jonathan M.; Perez, Miguel A.; McClafferty, Julie A. (Virginia Tech Transportation Institute, 2016-04)
      The focus of this project was to identify and prepare crash, near-crash, and baseline data sets extracted from the Second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS) trip files, then to ...
    • Determination of the In-Place Hot-Mix Asphalt Layer Modulus for Rehabilitation Projects Using a Mechanistic-Empirical Procedure 

      Loulizi, Amara; Flintsch, Gerardo W.; McGhee, Kevin K. (Virginia Center for Transportation Innovation and Research, 2006-07-01)
      This project evaluated the procedures proposed by the Mechanistic-Empirical Pavement Design Guide (MEPDG) to characterize existing hot-mix asphalt (HMA) layers for rehabilitation purposes. Thirty-three cores were extracted ...
    • Developing a Network-Level Structural Capacity Index for Structural Evaluation of Pavements 

      Bryce, J.; Flintsch, G.W.; Katicha, Samer W.; Diefenderfer, B.K. (Virginia Center for Transportation Innovation and Research, 2013-03-01)
      The objective of this project was to develop a structural index for use in network-level pavement evaluation to facilitate the inclusion of the pavement's structural condition in pavement management applications. The primary ...
    • Development of a Framework for Evaluating Yellow Timing at Signalized Intersections 

      Hesham Rakha; Ihab El-Shawarby; Ahmed Amer (Virginia Center for Transportation Innovation and Research, 2011-02-01)
      Studies show that the proper design of clearance intervals has significant implications for intersection safety. For example, in 2001, approximately 218,000 red-light-running crashes occurred at signalized intersections ...
    • Evaluation of the Cargill Safelane Surface Overlay 

      Sprinkel, Michael M.; Daniel S. Roosevelt; Flintsch, Gerardo W.; de León Izeppi, Edgar; Mokarem, David W. (Virginia Center for Transportation Innovation and Research, 2009-02-01)
      A recent development in polymer concrete overlays is the Cargill SafeLane surface overlay (SafeLane overlay). The 3/8-in-thick overlay is constructed with epoxy and broadcast aggregates, as are typical multiple-layer epoxy ...
    • Evaluation of Traffic Responsive Control on the Reston Parkway Arterial Network 

      Abbas, Montasir; Abdelaziz, Sherif (Virginia Center for Transportation Innovation and Research, 2009-02-01)
      Traffic responsive plan selection (TRPS) control is considered an effective operational mode in traffic signal systems. Its efficiency stems from the fact that it can capture variations in traffic patterns and switch timing ...
    • Fatigue Life Characterization of Superpave Mixtures at the Virginia Smart Road 

      Al-Qadi, Imad L.; Diefenderfer, Stacey D.; Loulizi, Amara (Virginia Center for Transportation Innovation and Research, 2005-08)
      Laboratory fatigue testing was performed on six Superpave HMA mixtures in use at the Virginia Smart Road. Evaluation of the applied strain and resulting fatigue life was performed to fit regressions to predict the fatigue ...
    • Field Investigation of High Performance Pavements in Virginia 

      Flintsch, Gerardo W.; Imad L. Al-Qadi; Loulizi, Amara; Samer Lahouar; McGhee, Kevin K.; Trenton Clark (Virginia Center for Transportation Innovation and Research, 2005-01-01)
      This study evaluated 18 pavement sections located in high-traffic highways in Virginia to find a premium pavement design with a life span of 40 years or more using current and past field experience. The selected pavement ...
    • Field Performance of High Friction Surfaces 

      de León Izeppi, Edgar; Flintsch, Gerardo W.; McGhee, Kevin K. (Virginia Center for Transportation Innovation and Research, 2010-06-01)
      This report describes an evaluation of high friction surface (HFS) systems. The goal of this evaluation was to develop guidance for agencies when considering whether an HFS was an appropriate solution when addressing ...
    • Ground-Penetrating Radar Calibration at the Virginia Smart Road and Signal Analysis to Improve Prediction of Flexible Pavement Layer Thicknesses 

      Imad L. Al-Qadi; Samer Lahouar; Loulizi, Amara (Virginia Center for Transportation Innovation and Research, 2005-01-01)
      A ground-penetrating radar (GPR) system was used to collect data over the different pavement sections of the Virginia Smart Road from June 1999 until December 2002. Three antennae at different frequencies were used for ...
    • High-speed texture measurement of pavements 

      McGhee, Kevin K.; Flintsch, Gerardo W. (Virginia Center for Transportation Innovation and Research, 2003-02-01)
      This study was conducted to validate high-speed texture measuring equipment for use in highway applications. The evaluation included two high-speed systems and a new static referencing device. Tests were conducted on 22 ...
    • Identification of Consented Driver Trips in the SHRP 2 Naturalistic Driving Study Data Set 

      McClafferty, Julie A.; Perez, Miguel A.; Hankey, Jonathan M. (Virginia Tech Transportation Institute, 2015-02)
      The Second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS) data set contains approximately 5.51 million naturalistic driving trip files across thousands of consented drivers, making it the ...
    • Improvement of Conspicuity of Trailblazing Signs: Phase III-Evaluation of Fluorescent Colors 

      Neale, Vicki L.; Anders, Richard L.; Christopher S. Schreiner; Brich, Stephen C. (Virginia Center for Transportation Innovation and Research, 2001-02)
      This report represents a Phase III effort to design and evaluate a new sign design for incident route trailblazing. The colors evaluated were fluorescent coral, fluorescent purple, fluorescent yellow-green, and non-fluorescent ...
    • Infrastructure Pavement Assessment & Management Applications Enabled by the Connected Vehicles Environment – Proof-of-Concept 

      Flintsch, Gerardo; Smith, Brian (Research and Innovative Technology Administration, 2015-09-30)
      The objective of this project was to develop prototypes and conduct a field test of system level applications of a connected vehicle pavement condition measurement system. This allowed the research team to: (1) investigate ...
    • Intersection Decision Support: Evaluation of a Violation Warning System to Mitigate Straight Crossing Path Collisions 

      Neale, Vicki L.; Perez, Miguel A.; Doerzaph, Zachary R. (Zachary Richard); Lee, Suzanne E.; Stone, Scott; Dingus, Thomas A. (Virginia Center for Transportation Innovation and Research, 2006-04)
      This project entailed the design, development, testing, and evaluation of intersection decision support (IDS) systems to address straight crossing path (SCP) intersection crashes. This type of intersection crash is responsible ...