• Login
    View Item 
    •   SMARTech Home
    • Georgia Tech Theses and Dissertations
    • Georgia Tech Theses and Dissertations
    • View Item
    •   SMARTech Home
    • Georgia Tech Theses and Dissertations
    • Georgia Tech Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Optimal Ramp Metering of Freeway Corridors

    Thumbnail
    View/Open
    CHILUKURI-DISSERTATION-2015.pdf (2.421Mb)
    Date
    2015-11-19
    Author
    Chilukuri, Bhargava Rama
    Metadata
    Show full item record
    Abstract
    Ramp meters have been used for congestion management on freeways since the 1960s to maximize freeway capacity by controlling on-ramp flows. Traditionally, the focus has been to develop rule-based algorithms and optimal control case studies. This led to a host of algorithms and methods which cannot be proven to provide an optimal control and the case studies does not provide a systematic understanding of the characteristics of optimal control and its influence on traffic dynamics. Moreover, optimal is not easy to achieve in practice due to the limited storage on the on-ramps. Towards this end, this dissertation systematically studies the optimality conditions for the case of unlimited storage and spatiotemporal evolution of control and its corresponding traffic dynamics on freeway and ramps under queue constraint, carefully taking the traffic dynamics into account. A Kinematic Wave model of the freeway-ramps system is optimized for minimal total delay. The optimality conditions for the case of unlimited ramp storage are studied using Moskowitz functions that provide several interesting insights for different scenarios, including the case of limited storage. This dissertation shows that the current problem posed as a nonlinear coupled PDE system with a nonlinear merge model cannot be solved analytically. This study also shows that the discrete-time nonlinear formulation solved with simulation-based optimization does not converge in reasonable time. To overcome this, the problem is reposed as a LP formulation that includes capacity drop. For discrete formulation, this study develops an error-free solution to the KW model with a source term that enhanced the quality of the numerical solution. This study identifies four distinct regions in the state surface with distinct metering patterns. Explicit modeling of ramps enabled correlating the initialization and termination times of the metering patterns with the evolution of traffic dynamics on the freeways and ramps. Using these results, this dissertation presents a hybrid isolated ramp metering algorithm that outperforms existing methods.
    URI
    http://hdl.handle.net/1853/56204
    Collections
    • Georgia Tech Theses and Dissertations [23403]
    • School of Civil and Environmental Engineering Theses and Dissertations [1723]

    Browse

    All of SMARTechCommunities & CollectionsDatesAuthorsTitlesSubjectsTypesThis CollectionDatesAuthorsTitlesSubjectsTypes

    My SMARTech

    Login

    Statistics

    View Usage StatisticsView Google Analytics Statistics
    facebook instagram twitter youtube
    • My Account
    • Contact us
    • Directory
    • Campus Map
    • Support/Give
    • Library Accessibility
      • About SMARTech
      • SMARTech Terms of Use
    Georgia Tech Library266 4th Street NW, Atlanta, GA 30332
    404.894.4500
    • Emergency Information
    • Legal and Privacy Information
    • Human Trafficking Notice
    • Accessibility
    • Accountability
    • Accreditation
    • Employment
    © 2020 Georgia Institute of Technology