THE ESTABLISHMENT OF PRIORITIES FOR HIGHWAY IMPROVEMENT PROGRAMS

METHODS OF DETERMINING MATHEMATICAL "RATINGS" OF "INDICES" TO GUIDE IN THE SELECTION OF PRIORITIES OF IMPROVEMENTS ARE GIVEN AND THEIR LIMITATIONS ARE DISCUSSED. MAJOR IMPROVEMENTS TO EXISTING SURFACED ROADS, EXCLUSIVE OF BRIDGE AND GRADE SEPARATION PROJECTS, ARE CLASSED AS (1) WIDENING; (2) STRENGTHENING OR RECONSTRUCTION; AND (3) RELOCATION. SEPARATE PRIORITY INDICES FOR EACH OF THESE IMPROVEMENTS ARE DETERMINED. UNDER WIDENING ARE INCLUDED (A) WIDENING TO MULTIPLE LANES, AND (B) WIDENING OF NARROW 2-LANE SURFACES. FROM AN ANALYSES OF YEARLY TRAFFIC BY HOURS AND THE TIMES WHEN THE TRAFFIC VOLUME WAS IN EXCESS OF 300 VEHICLES PER HOUR, THE INDEX FOR GUIDANCE IN WIDENING TO MULTIPLE LANES IS GIVEN AS "THE NUMBER OF VEHICLES USING THE ROAD IN THE COURSE OF A YEAR DURING THOSE TIMES WHEN THE TRAFFIC VOLUME WAS IN EXCESS OF THE NUMBER OF VEHICLES PER HOUR CONSIDERED TO BE THE MAXIMUM FOR A 2-LANE ROAD BEFORE WIDENING. FOR WIDENING NARROW 2-LANE SURFACES THE INDEX USED IS THE 24 HOUR TRAFFIC ON ANY GIVEN ROAD SECTION DIVIDED BY THE AVERAGE TRAFFIC ON ROADS OF THE SAME WIDTH. THE INDEX FOR STRENGTHENING AND RECONSTRUCTION IS THE SURFACE MAINTENANCE COST OF ANY GIVEN ROAD SECTION DIVIDED BY THE STATE AVERAGE COST FOR SURFACES OF THE SAME TYPE. SURFACE TYPES ARE GROUPED INTO A FEW GENERAL CLASSES, AND THIS CLASSIFICATION SHOULD BE DETERMINED BY EACH STATE RATHER THAN ON A NATIONAL BASIS. WIDE DIVERSITY OF SURFACE TYPE MAKES THIS NECESSARY. BASED ON THE FACT THAT RESTRICTED SIGHTS BECOME MORE HAZARDOUS AND MORE OBJECTIONABLE AS TRAFFIC INCREASES, THE INDEX FOR RELOCATION IS THE INDEX FOR WIDENING MULTIPLIED BY THE NUMBER PER MILE OF RESTRICTED SIGHT DISTANCES UNDER 500 FEET ON ANY GRIVEN ROAD SECTION AND DIVIDED BY THE STATE AVERAGE NUMBER PER MILE ON THE SAME SYSTEM. AFTER THE INDICES FOR THE THREE GENERAL CLASSES OF IMPROVEMENT ARE ESTABLISHED, THEY ARE CONSIDERED INDIVIDUALLY AND IN COMBINATION WITH EACH OTHER TO DETERMINE BOTH THE TYPE OF IMPROVEMENT MOST DESIRABLE AND ITS PRIORITY. THESE METHODS, ALTHOUGH SUBJECT TO SOME CRITICISM OFFER APPRECIABLE BENEFIT TO HIGHWAY OFFICIALS BY NARROWING THE FIELD IN WHICH JUDGMENT ALONE NEEDS TO BE EXERCISED IN DETERMINING THE PRIORITIES FOR ANNUAL IMPROVEMENT PROGRAMS. /AUTHOR/

  • Supplemental Notes:
    • Vol 20, pp 115 - 120, 3 TAB
  • Authors:
    • Marye, B
  • Publication Date: 1941

Media Info

  • Monograph Title: Proceedings of the Twentieth Annual Meeting of the Highway Research Board Held at Washington, D.C. December 3-6, 1940
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00200445
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Aug 23 1971 12:00AM