COMPARISON OF AASHO AND TEXAS TEST METHODS AND SPECIFICATIONS FOR FLEXIBLE BASE MATERIALS

A COOPERATIVE STUDY OF FLEXIBLE BASE PERFORMANCE AND TESTING PROCEDURES WAS MADE BY THE TEXAS HIGHWAY DEPARTMENT AND THE BUREAU OF PUBLIC ROADS TO COMPARE LIQUID LIMIT AND PLASTICITY INDEX TEST RESULTS FOR A SUITABLE RANGE OF FLEXIBLE BASE MATERIALS USING THE WET AND DRY METHODS OF SAMPLE PREPARATION, AND TO CONDUCT A STUDY OF THE PERFORMANCE OF EXISTING FLEXIBLE BASE COURSES. FORTY-TWO SAMPLES OF VARIOUS TYPES OF FLEXIBLE BASE MATERIALS WERE COLLECTED FROM VARIOUS PARTS OF TEXAS AND PROCESSED BY SPLITTING EACH SAMPLE INTO TWO NEARLY IDENTICAL PORTIONS, ONE OF WHICH WAS SENT TO THE BPR LABORATORY IN WASHINGTON, D. C. AND THE OTHER RETAINED IN TEXAS. SMALL SAMPLES OF SOIL BINDER WHICH WERE OBTAINED BY EACH LABORATORY WERE EXCHANGED . EACH LABORATORY PERFORMED TEST FOR SOIL CONSTANTS AND SOME SIEVE SIZE ANALYSIS ON ALL SAMPLES. A STUDY OF THE RELATION OF SOIL CONSTANTS AND ROAD PERFORMANCE WAS ALSO MADE. RESULTS OF THE INVESTIGATION INDICATE THAT OPERATORS FROM THE LABORATORIES ARE IN REASONABLY CLOSE AGREEMENT ON LIQUID LIMIT AND PLASTICITY INDEX VALUES SO LONG AS THEY ARE TESTING THE SAME MINUS NO. 40 MATERIAL. THIS WAS NOT FOUND TO BE THE CASE WHEN OPERATORS DID THEIR OWN PREPARATION AND TESTING. THE DIFFERENCE IN PLASTICITY INDEX PRODUCED BY USE OF TWO DIFFERENT PREPARATION METHODS /WET AND DRY/ CAN BE EXPECTED TO BE AS MUCH AS FOUR OR FIVE POINTS. THE DATA OBTAINED FROM ROADS OF KNOWN BEHAVIOR DO NOT SHOW ANY CORRELATION BETWEEN THE SOIL CONSTANTS AND PAVEMENT PERFORMANCE.

  • Supplemental Notes:
    • Hpr-1/5/, 48 /STATE/
  • Corporate Authors:

    Texas State Department of Highways & Public Transp

    11th and Brazos Streets
    Austin, TX  United States  78701
  • Authors:
    • McDowell, C
  • Publication Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 00230591
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS, STATEDOT
  • Created Date: Aug 15 2004 2:18AM