HISTORY OF MEDIAN DEVELOPMENT IN ILLINOIS

DESIGNS FOR MEDIANS OF DIVIDED HIGHWAYS HAVE GONE THROUGH AN EXTENDED PERIOD OF DEVELOPMENT INVOLVING THE TRIAL INSTALLATION OF MANY DIFFERENT MEDIAN WIDTHS AND CROSS- SECTIONS. A SUMMARY OF SUCH ACTIVITY IN ILLINOIS IS PRESENTED. AFTER YEARS OF EXPERIMENTING WITH DIFFERENT WIDTHS OF MEDIANS FOR RURAL HIGHWAYS IT WAS DECIDED THAT A 40-FOOT WIDTH WAS THE DESIRABLE MINIMUM. WHERE POSSIBLE, MEDIANS WIDER THAN THIS MINIMUM ARE NOW USED BECAUSE OF DECREASE IN HEADLIGHT GLARE, REDUCTION IN CROSS-MEDIAN ACCIDENTS, AND FREQUENT ECONOMICAL IMPROVEMENT IN ROADWAY ALIGNMENT. HOWEVER, IN MOST CASES IN CONSTRUCTING A HIGH- WAY WITH FULL CONTROL OF ACCESS IN URBAN AREAS, IT IS CONSIDERED NECESSARY TO USE A NARROWER MEDIAN AND CONSIDER THE INSTALLATION OF A SUITABLE MEDIAN BARRIER. FOR ROUTES WITH NO CONTROL OF ACCESS IN CITIES, THE COST OF RIGHT-OF- WAY NORMALLY LIMITS THE DESIGN TO THE NARROW MEDIAN TYPES, OR TO NO MEDIAN AT ALL. IT IS CURRENTLY BELIEVED THAT AN EASILY MOUNTED OR FLUSH-TYPE BARROW MEDIAN SHOULD NOT BE USED WHERE THERE IS NEED FOR NUMEROUS LEFT-TURN MOVEMENTS. SUCH MOVEMENTS SHOULD BE LIMITED TO INTERSECTIONS OR PROVIDED FOR BY THE CONSTRUCTION OF ADEQUATE LEFT-TURN LANES IN THE MEDIAN.

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  • Authors:
    • Hutchinson, John W
    • Kennedy, Thomas W
    • Surman, Hugo E
  • Publication Date: 1966

Media Info

  • Media Type: Print
  • Features: Figures; References;
  • Pagination: pp 50-84
  • Monograph Title: Traffic control: Devices and Delineation
  • Serial:

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Filing Info

  • Accession Number: 00203102
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Sep 29 1994 12:00AM