ECONOMICS OF LOW COST HIGHWAY BRIDGES

A RATHER STRONG CASE IS MADE FOR THE TREATED TIMBER BRIDGE IN SHORT SPAN LENGTHS BY MR. SEILER IN HIS PAPER ON TREATED TIMBER TRESTLES. HE CAREFULLY REFRAINS FROM A DISCUSSION OF LONGER SPAN POSSIBILITIES. THE DISCUSSER FEELS THAT HE HAS FAILED TO TAKE INTO ACCOUNT THE VALUE OF ARCHITECTURAL POSSIBILITIES AND HAS MADE TOO MUCH OF THE MATTER OF OBSOLESCENCE. HE IS SOMEWHAT OVERLY OPTIMISTIC REGARDING AVERAGE MAINTENANCE EXPENSE FOR TREATED TIMBER. AN EXCELLENT CASE WAS MADE BY MR. FRANKLAND FOR LOW COST STEEL HIGHWAY BRIDGES. HOWEVER, THE DISCUSSER FEELS THAT HE HAS SHOWN A TENDENCY TO MINIMIZE MAINTENANCE COSTS AND IN THE CASE OF THE STEEL PILE BRIDGE, TO EXTEND THE USE OF STEEL INTO A FIELD WHERE THE POSSIBILITY OF ITS SUCCESSFUL COMPETITION IS PROBLEMATICAL. MR. FLEMING'S PAPER ON THE USE OF CONCRETE AS AN ECONOMIC HIGHWAY BRIDGE MATERIAL PRESENTS A COMPLETE ECONOMIC ANALYSIS, BUT HAS USED A PERCENTAGE RATE FOR MAINTENANCE PLUS AMORTIZATION FOR CREOSOTED TIMBER WHICH PLACES THIS MATERIAL AT A DISADVANTAGE. THE DESCRIPTION OF IMPROVED DETAILS, AND REVIEW OF CURRENT DESIGN PRACTICE ARE HIGHLY INSTRUCTIVE. HOWEVER, IN ADVOCATING THE USE OF PERMANENT CONSTRUCTION FOR LATERAL ROADS, HE APPEARS TO ATTEMPT THE EXTENSION OF CONCRETE SLIGHTLY BEYOND ITS TRUE FIELD OF ECONOMIC UTILITY. EACH OF THE PAPERS DISCUSSED CONSTITUTES A DIRECT CONTRIBUTION TO AVAILABLE ENGINEERING LITERATURE PERTINENT TO HIGHWAY BRIDGE TYPES; EACH OF THE AUTHORS HAS MADE AN EXCELLENT PRIMA FACIE CASE FOR THE PARTICULAR STRUCTURAL MATERIAL DISCUSSED, AND HAS BEEN RATHER FAIR IN HIS STATEMENTS.

  • Supplemental Notes:
    • Vol 11, Pt 1, PP 114-123, 2 FIG, 2 TAB; part of Report of Committee on Highway Design: A Symposium on the Economics of Low Cost Highway Bridges
  • Authors:
    • Mccullough, C B
  • Publication Date: 1932

Media Info

  • Monograph Title: Proceedings of the Eleventh Annual Meeting of the Highway Research Board Held at Washington, D.C. December 10-11, 1931. Part I: Reports of Research Committees and Papers
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00209264
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jun 29 1971 12:00AM