EVALUATION OF PAVEMENT DESIGN IN VIRGINIA BASED ON LAYER DEFLECTIONS, SUBGRADE AND ITS MOISTURE CONTENT

THE OPTIMUM STRUCTURAL STRENGTH CONTRIBUTED BY A MATERIAL TO THE OVERALL STRENGTH OF THE PAVEMENT WAS STUDIED FOR CASES APPLICABLE TO VIRGINIA. THE VARIABLES WERE (1) THE MODULUS OF ELASTICITY OR THE THICKNESS EQUIVALENCY OF THE MATERIAL, (2) THE THICKNESS OF THE MATERIAL IN THE LAYER, (3) THE LOCATION OF THE MATERIAL WITH RESPECT TO OTHER LAYERS CONTAINING STRONGER OR WEAKER MATERIALS AND IN VARYING THICKNESSES, AND (4) THE EFFECT OF THE TOTAL PAVEMENT THICKNESS AND THE DEPTH OF THE MATERIAL FROM THE TOP OF THE PAVEMENT. THE INVESTIGATION CONSISTED: (1) A STUDY OF THE THICKNESS EQUIVALENCIES OF THE MATERIALS ON INTERSTATE, PRIMARY, SECONDARY AND SUBDIVISION ROADS IN VIRGINIA. AND (2) A MODEL STUDY. THE EVALUATION OF THE HIGHWAY SYSTEM WAS QUANTITATIVE, WHILE THAT OF THE MODEL STUDY WAS QUALITATIVE ONLY. THIS INVESTIGATION SHOWED THAT THE STRUCTURAL STRENGTH OF A PAVEMENT IS DECREASED WHEN A WEAKER LAYER IS PLACED OVER A STRONGER LAYER OR WHEN A WEAKER LAYER IS SANDWICHED BETWEEN TWO STRONG LAYERS. THE INVESTIGATION ALSO SHOWED THAT WHEN THE BOTTOM OF THE TOP LAYER DOES NOT BEND, THE STRESS DISTRIBUTION IS BULB TYPE; AND WHEN THE BOTTOM BENDS, THE STRESS DISTRIBUTION IS FAN TYPE. EACH CASE WOULD, THEREFORE, NEED A DIFFERENT MATHEMATICAL TREATMENT FOR DESIGN. /AUTHOR/

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• Record URL:
  • https://rosap.ntl.bts.gov/view/dot/19519
• Corporate Authors:

  Virginia Department of Highways

  Richmond, VA  United States  23219

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Vaswani, N K
• Publication Date: 1970-7

Subject/Index Terms

• TRT Terms: Building materials; Deflection; Deformation curve; Modulus of elasticity; Pavement design; Pavement performance; Pavements; Primary highways; Secondary roads; Soil water; Subgrade (Pavements); Thickness
• Identifier Terms: Interstate Highway System
• Uncontrolled Terms: Pavement thickness
• Old TRIS Terms: Layered system mechanics; Subgrade moisture
• Subject Areas: Highways; Pavements;

Filing Info

• Accession Number: 00206422
• Record Type: Publication
• Source Agency: Federal Highway Administration
• Files: TRIS, USDOT, STATEDOT
• Created Date: Oct 19 1970 12:00AM