DETERMINATION OF LINE AND GRADE FOR NEW LOW-VOLUME ROADS: IMPLICATIONS OF A TOTAL-COST APPROACH

The selection of general alignment and gradient for a road is posed as a unique design decision driven by the objective of minimizing total life-cycle costs of construction and vehicle operation. Inputs to the design decision process include the terrain between the origin and destination; the roadway geometry and surface type; the vehicle volume, mix, and growth rate; unit construction and vehicle operating costs; design life; and interest rate. Outputs include combinations of horizontal alignments and piecewise gradients, representing various optima based on combinations of the life-cycle cost components. These outputs provide the basis for the subsequent design decisions. The analytical procedure includes a basic cost model that reduces the terrain to a number of grade-constrained construction surfaces by using linear programming and a route selection model that computes the life-cycle costs of various alternative alignments over the surfaces and selects the ones with the least cost by using shortest path and next-best path techniques. The implications of a total-cost approach for horizontal and vertical design standards are discussed. The overall implication, however, is the potential obsolescence of predetermined geometric design standards for other than urban roads and intersections, because these standards can be uniquely determined as outputs of an analytical process.

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/trr/1991/1291vol1/1291-039.pdf
• Record URL:
  • https://scholar.google.com/scholar_lookup?title=DETERMINATION+OF+LINE+AND+GRADE+FOR+NEW+LOW-VOLUME+ROADS%3A+IMPLICATIONS+OF+A+TOTAL-COST+APPROACH&author=N.+Parker&publication_year=1991
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/030905715
• Supplemental Notes:
  • This paper appears in Transportation Research Record No. 1291, Fifth International Conference on Low-Volume Roads, May 19-23, 1991, Raleigh, North Carolina, Volume 2. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Parker, Neville A
• Conference:
  • International Conference on Low-Volume Roads, 5th, 1991, Raleigh, North Carolina, USA
• Publication Date: 1991

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 3-14
• Monograph Title: Fifth International Conference on Low-Volume Roads May 19-23 1991, Raleigh, North Carolina, USA; volumes 1 and 2
• Serial:
  • Transportation Research Record
  • Issue Number: 1291
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Alignment; Conferences; Design standards; Highway grades; Life cycle analysis; Life cycle costing; Low volume roads; Mathematical models; Optimization; Slopes
• Subject Areas: Design; Finance; Highways; Planning and Forecasting; I21: Planning of Transport Infrastructure;

Filing Info

• Accession Number: 00611777
• Record Type: Publication
• ISBN: 030905715
• Files: TRIS, TRB, ATRI
• Created Date: Aug 31 1991 12:00AM