ROAD DESIGN AND DYNAMIC LOADING

THIS REPORT OF TEN YEARS OF DYNAMIC TESTING OF FLEXIBLE PAVEMENT FOUNDATIONS SHOWS THAT ELASTIC MODULUS OF SOILS AND UNBOUND FOUNDATION MATERIALS CAN BE MEASURED BY MEANS OF CONTINUOUS VIBRATIONS OF ARBITRARY FREQUENCIES, VARIATIONS OF WHICH ENABLE MEASUREMENTS AT VARIOUS DEPTHS. THE DYNAMIC POISSON RATIO WAS FOUND TO BE ABOUT 0.4 AND INFLUENCE OF DAMPING AND MASS FOUND TO BE USUALLY LESS THAN 20 PER CENT OF STIFFNESS OF TOTAL ROAD CONSTRUCTION. A RELATIONSHIP BETWEEN THE MODULI OF UNBOUND FOUNDATION MATERIALS AND THE SUBGRADE IS ESTABLISHED. THE DYNAMIC MODULI OF SOILS WAS FOUND TO BE 2 TO 3 TIMES STATIC VALUES. ELASTIC MODULI OF BITUMINOUS /PLASTIC/ MATERIALS AT LOW TEMPERATURES CAN BE DETERMINED BY LABORATORY DYNAMIC METHODS. CALCULATED DEFORMATIONS BY THE THEORY FOR STATIC LOADS, TAKING INTO ACCOUNT RELATIONSHIPS BETWEEN STATIC AND DYNAMIC LOADING, ARE IN GOOD AGREEMENT WITH ACTUAL VALUES MEASURED UNDER MOVING TRAFFIC LOADS AND DEMONSTRATE THAT STATIC THEORIES MAY BE APPLIED TO DYNAMIC TRAFFIC LOADS. DYNAMIC LOADING IS FOUND TO PROVIDE A MEANS OF APPLICATION OF AVAILABLE STATIC THEORIES TO PAVEMENT STRUCTURE DESIGN. TO SOLVE PROBLEMS CONNECTED WITH CRACKING AND SETTLEMENT, THEORIES ON STRESSES AND STRAINS IN STRATIFIED ELASTIC SYSTEMS ARE USED, WHILE PLASTIC DEFORMATION IN THE PAVEMENT IS GENERALLY CONSIDERED MAINLY IN CONNECTION WITH MATERIAL PROPERTIES. THE THEORIES ARE VALID FOR STATIC LOADING, WHEREAS THE TRAFFIC LOAD IS PREDOMINANTLY DYNAMIC IN CHARACTER. FOR THAT REASON THE STATIC THEORY MAY NOT BE APPLIED TO ROAD CONSTRUCTIONS WITHOUT TAKING INTO ACCOUNT THE TYPICAL DIFFERENCES BETWEEN STATIC AND DYNAMIC LOADING. IN THE PRESENT PAPER SPECIAL ATTENTION IS PAID TO THIS ASPECT. /NAPA/

• Supplemental Notes:
  • Vol33, Pp92-125
• Authors:
  • Heukelom, W
  • Klomp, A J
• Conference:
  • Assoc Asphalt Paving Technol Proc
• Publication Date: 1964-2

Subject/Index Terms

• TRT Terms: Asphalt concrete; Deflection tests; Dynamic loads; Dynamic tests; Flexible pavements; Foundation soils; Foundations; Frequency (Electromagnetism); Modulus of elasticity; Pavement cracking; Pavement design; Pavements; Plastic deformation; Poisson ratio; Sampling; Settlement (Structures); Static loads; Subgrade (Pavements); Thickness; Vibration
• Old TRIS Terms: Continuous sampling; Layered system mechanics; Pavement course thickness; Poissons ratio; Static loading
• Subject Areas: Geotechnology; Highways; Pavements;

Filing Info

• Accession Number: 00206223
• Record Type: Publication
• Source Agency: National Asphalt Pavement Association (NAPA)
• Files: TRIS
• Created Date: Mar 21 1994 12:00AM