REPORT OF COMMITTEE ON FLEXIBLE TYPE SURFACES, WHAT WE KNOW ABOUT THE DESIGN OF PAVEMENTS OF THE FLEXIBLE TYPE

A DIGEST AND DISCUSSION OF PUBLISHED MATERIAL ON FLEXIBLE PAVEMENT DESIGN WAS PRESENTED. IT WAS FELT THAT ADEQUATE INFORMATION WAS LACKING CONCERNING THE QUANTITATIVE BEARING CAPACITY OF SUBGRADES, AT LEAST THE TYPE OF INFORMATION SUITABLE FOR USE IN DESIGN FORMULAS. THE FORMULAS WERE BASED ON THE STATIC APPROACH ALTHOUGH PRESSURES IMPOSED ON SUBGRADES ARE SELDOM PURELY STATIC. PRESSURE DISTRIBUTION MAY NOT ONLY DEPEND UPON THE CHARACTER OF THE SUBGRADE SOIL BUT TO A MARKED EXTEND UPON THE DEGREE OF FLEXIBILITY OF THE ROAD SURFACE. THE MORE THE FACTOR OF SUBGRADE SUPPORT ENTERS INTO THE PERFORMANCE OF A ROAD SURFACE THE MORE NECESSARY IT BECOMES TO TAKE INTO ACCOUNT THE DYNAMIC PROPERTIES OF THE SUBGRADE SOIL. A GERMAN OSCILLATOR METHOD OF TESTING APPEARED TO HAVE POSSIBILITIES FOR STUDYING THE DYNAMIC PROPERTIES OF SOILS AND ROAD SURFACES. METHODS OF DESIGN OF FLEXIBLE PAVEMENTS WERE CONSIDERED AS PREMISED MORE UPON THEORETICAL CONCEPTIONS OF SOIL RESISTANCE AND PRESSURE DISTRIBUTION THAN UPON PERTINENT OR COMPREHENSIVE TEST DATA. MAJOR PARTS OF THE GENERAL PROBLEM THAT NEEDED ATTENTION WERE ITEMIZED. THEY INCLUDE: (1) A STUDY OF THE LOAD SUPPORTING AND PRESSURE-DISTRIBUTING ABILITY OF TYPICAL SURFACES OF THE NONRIGID TYPE, (2) THE DEVELOPMENT OF DATA THAT INDICATED MORE DIRECTLY THE SAFE LOAD-SUPPORTING VALUE OF SOILS WHEN SUBJECT TO FORCES AND DISPLACEMENTS SUCH AS OBTAINED UNDER ROAD SURFACES OF THE NON-RIGID TYPE, AND (3) THE DETERMINATION OF THE RELATIVE EFFECTS OF SLOWLY APPLIED AND SUDDENLY APPLIED FORCES IN ORDER THAT THE CRITICAL LOAD FOR DESIGN PURPOSES MAY BE KNOWN.

• Record URL:
  • https://onlinepubs.trb.org/Onlinepubs/hrbproceedings/17/17Pt1-009.pdf
• Supplemental Notes:
  • Vol 17, ParT I, PP 144-148; part of Report of Department of Design. 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:
  • Benkelman, A C
  • Krynine, D P
  • Buchanan, J A
  • Smith, R
• Publication Date: 1938

Media Info

• Media Type: Digital/other
• Monograph Title: Proceedings of the Seventeenth Annual Meeting of the Highway Research Board Held at Washington, D.C. November 30, December 1, 2, 3, 1937. Part I
• Serial:
  • Highway Research Board Proceedings
  • Volume: 17
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Bearing capacity; Critical values; Dynamics; Flexibility; Flexible pavements; Formulas; Loads; Methodology; Pavement design; Pressure; Properties of materials; Signal generators; Soils; Static pressure; Subgrade (Pavements); Surface course (Pavements)
• Uncontrolled Terms: Critical loads; Pressure distribution
• Old TRIS Terms: Oscillators; Soil characteristics
• Subject Areas: Geotechnology; Highways; Materials; Pavements;

Filing Info

• Accession Number: 00205826
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Aug 15 1971 12:00AM