The Folded Interchange: An Unconventional Design for the Reconstruction of Cloverleaf Interchanges

This paper presents the Folded Interchange design and compares its relative advantages and disadvantages between unconventional and conventional interchanges. Proper selection of interchange type must maintain a balance between safety, operations, environmental and right-of- way impacts, and costs. Many of the existing interchanges that will be reconstructed as the US infrastructure ages are cloverleaf interchanges at the intersection of a freeway and an arterial roadway. The cloverleaf interchange is typically plagued by accident and congestion problems in its weaving sections on both the freeway and arterial roadways. On the arterial roadway, there are typically signalized intersections abutting the interchange, further complicating the weave and merge movements and causing additional accidents and traffic congestion. The Folded Interchange is ideally suited for the reconstruction of failing cloverleaf interchanges between a full-control-of-access freeway and an arterial roadway. The Folded Interchange combines some of the elements of the diverging diamond and continuous flow interchange elements to optimize operational efficiency while maintaining the basic footprint of the existing cloverleaf interchange to minimize costs and impacts. This paper is the summary of observations from two case studies involving interchange selection where the Folded Interchange was selected as the preferred alternate. The studies considered traffic and operations analyses, right-of-way and environmental impacts, and construction costs. In each of the case studies, the Folded Interchange offered superior traffic operational performance, with lower costs and fewer right-of-way and environmental impacts compared to other conventional and unconventional interchanges evaluated for freeway-to-arterial intersections.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9781933452470
• Corporate Authors:

  Institute of Transportation Engineers (ITE)

  Washington, DC  United States 
• Authors:
  • Riniker, Keith A
• Conference:
  • ITE 2009 Technical Conference and Exhibit
  • Location: Phoenix AZ, United States
  • Date: 2009-3-22 to 2009-3-25
• Publication Date: 2009

Language

• English

Media Info

• Media Type: CD-ROM
• Features: Figures; Tables;
• Pagination: 11p
• Monograph Title: ITE 2009 Technical Conference and Exhibit. Transportation Operations in Action. Compendium of Technical Papers

Subject/Index Terms

• TRT Terms: Arterial highways; Cloverleaf interchanges; Diamond interchanges; Environmental impacts; Highway operations; Right of way (Traffic); Road construction; Single point urban interchanges
• Geographic Terms: Baltimore (Maryland); Frederick (Maryland)
• Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 01164352
• Record Type: Publication
• ISBN: 9781933452470
• Files: TRIS
• Created Date: Jul 30 2010 8:28AM