SANDSTONE ORIGIN SUBBASE MATERIAL STUDY

EXCEEDING THE SPECIFICATION LIMITS FOR THE FRACTION OF MATERIAL PASSING THE NO. 100 SIEVE HAS BEEN AN OCCASIONAL PROBLEM WITH SOME SUBBASE MATERIALS IN WISCONSIN OBTAINED FROM SANDSTONE. IT HAS NOT BEEN UNCOMMON FOR THESE MATERIALS TO EXCEED THE SPECIFICATION LIMITS FOR THE FRACTION PASSING THE NO. 100 SIEVE BY FIVE TO EIGHT PERCENTAGE POINTS WHILE REMAINING WITHIN THE LIMITS FOR THE NO. 200 SIEVE. IT WAS BELIEVED THAT THESE SANDSTONE MATERIALS WOULD PERFORM SATISFACTORILY ALTHOUGH NOT ENTIRELY CONFORMING TO THE GRADATION SPECIFICATIONS. A LIMITED LABORATORY INVESTIGATION WAS INITIATED TO DETERMINE THE EFFECT OF VARYING THE FRACTION OF MATERIAL PASSING THE NO. 100 SIEVE AND RETAINED ON THE NO. 200 SIEVE, BOTH INSIDE AND OUT OF SPECIFICATION LIMITS. THE TESTING PROGRAM INCLUDED DENSITY, PERMEABILITY, CAPILLARY RISE, DIRECT SHEAR AND PENETRATION DETERMINATIONS ON PREPARED SAMPLES OF SANDSTONE MATERIAL FROM TWO SOURCES. THE RESULTS OF THE INVESTIGATION INDICATED THAT INCREASING THE FRACTION OF MATERIAL PASSING THE NO. 100 SIEVE AND RETAINED ON THE NO. 200 SIEVE BY FIVE TO TEN PERCENTAGE POINTS WOULD NOT PRODUCE DETRIMENTAL EFFECTS WITH RESPECT TO BEARING CAPACITY AND DRAINAGE CHARACTERISTICS. AS A CONSEQUENCE, THE WISCONSIN HIGHWAY COMMISSIONS STANDARD SPECIFICATIONS FOR GRANULAR SUBBASE COURSE, GRADE 2, WERE AMENDED TO INCREASE THE MAXIMUM ALLOWABLE AMOUNT OF THE FRACTION PASSING THE NO. 100 SIEVE FROM 25 TO 30 PER CENT. /AUTHOR/

  • Supplemental Notes:
    • Hpr-1/3/, STATE 907
  • Corporate Authors:

    Wisconsin Department of Transportation

    Division of Highways, 3502 Kinsman Boulevard
    Madison, WI  USA  53704
  • Authors:
    • Dunn, K H
  • Publication Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 00230608
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS, STATEDOT
  • Created Date: Aug 15 2004 2:19AM