GRADATION AND OTHER EFFECTS ON PERFORMANCE OF BASE COURSE SUBJECTED TO HEAVY REPEATED ROLLING LOADS

PREVIOUS TESTS AT WEST VIRGINIA UNIVERSITY ON: (1) DETERMINATION OF THE MINIMUM THICKNESS OF SANDSTONE NECESSARY TO DISTRIBUTE A HEAVY WHEEL LOAD SATISFACTORILY TO THE SUBGRADE, (2) THE RELATIVE PERFORMANCE OF THE VARIOUS TYPES OF SANDSTONES FOUND IN THE STATE, AND (3) THE PERFORMANCE OF SEVERAL DIFFERENCE STABILIZING AGENTS WHEN USED WITH ONE TYPE OF SANDSTONE ARE SUMMARIZED. THE PRESENT INVESTIGATION STUDIES THE EFFECT OF GRADATION OF UNTREATED BASE CORES UPON PERFORMANCE. A COMPUTER ANALYSIS IS BEING MADE ON ALL DATA FROM ALL PHASES. THE GRADATIONS USED IN THE BASE COURSES OF THESE SPECIMENS ARE SHOWN IN FIGURES. LIMESTONE, AS WELL AS SANDSTONE BASE SPECIMENS WERE TESTED. MOST OF THE TESTS WERE CONDUCTED USING 9000 POUNDS WHEEL LOAD AND 85 PSI TIRE INFLATION PRESSURE. THE WHEEL PATH WIDTH DIFFERED IN SOME OF THE RESULTS BUT IN MOST CASES IT WAS 24 INCHES. THROUGH COMPUTER ANALYSIS ON THE PREVIOUS PHASES OF STUDY, THE MOST RELIABLE QUANTITY WITH WHICH CONSTRUCTION PARAMETERS HAVE BEEN CORRELATED HAS BEEN THE NATURAL LOGARITHM OF THE SLOPE OF THE DEFLECTION VS. (LOG) OF LOAD REPETITIONS CURVES. WHEN THESE VALUES AND THE GRADATIONS OF SPECIMENS OF THE PRESENT TESTS ARE COMPARED, NO DEFINITE TREND CAN BE PERCEIVED IN SPECIMEN PERFORMANCE. HOWEVER, THE DATA DOES OFFER SOLID EVIDENCE THAT A BROKEN GRADED OR GAPPED GRADED BASE REQUIRES A HIGHER GRADATION INDEX IN ORDER TO BRING ABOUT A PERFORMANCE EQUIVALENT TO SMOOTH GRADED BASES. IT IS HOPED THAT A MORE DEFINITE CORRELATION BETWEEN GRADATION AND PERFORMANCE WILL BE FOUND IF A MORE DESCRIPTIVE INDEX FOR GRADATION CAN BE FOUND.

• Supplemental Notes:
  • pp 143-147, 5 FIG
• Authors:
  • Haynes, R R
  • Worrell, D T
• Publication Date: 1967-11

Media Info

• Serial:
  • Southeast Assoc St Hwy Officials Proc

Subject/Index Terms

• TRT Terms: Accelerated tests; Aggregate gradation; Base course (Pavements); Data analysis; Information processing; Mathematical analysis; Motion; Motor vehicles; Pavement performance; Repeated loads; Sandstones; Stabilizers; Subgrade (Pavements); Wheel loads
• Uncontrolled Terms: Moving vehicles; Wheel load distribution
• Old TRIS Terms: Wheel path
• Subject Areas: Geotechnology; Highways;

Filing Info

• Accession Number: 00217788
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 4 1994 12:00AM