SAND EQUIVALENT TEST FOR CONTROL OF MATERIALS DURING CONSTRUCTION

A TEST METHOD IS PRESENTED WHICH PROVIDES A RAPID METHOD FOR DETECTING THE PRESENCE OR ABSENCE OF DETRIMENTAL FINES OR CLAY-LIKE MATERIALS IN SOILS AND MINERAL AGGREGATES. THE RELATIVE PROPORTIONS OF FINE MATERIAL AND SAND ARE COMPARED ON AN ARBITRARY VOLUME BASIS BY A SIMPLE TEST PROCEDURE WHICH TENDS TO MAGNIFY OR EXPAND THE VOLUME OF CLAY SOMEWHAT IN PROPORTION TO ITS DETRIMENTAL OR OBJECTIONABLE EFFECT. THE TEST IS APPLIED TO THE FRACTION OF MATERIAL PASSING THE NO. 4 SIEVE AND REQUIRES RELATIVELY SIMPLE EQUIPMENT. BRIEFLY THE TEST METHOD CONSISTS OF SHAPING THE MATERIAL TO BE TESTED IN A WEAK SOLUTION OF CALCIUM CHLORIDE. THE MATERIAL IS ALLOWED TO SETTLE IN THE SOLUTION FOR TWENTY MINUTES AND THE RELATIVE VOLUME OF SETTLED SAND IS DIVIDED BY THE TOTAL VOLUME OF CLAY PLUS SAND TO GIVE THE SAND EQUIVALENT RATIO. MATERIALS SUCH AS CLEAN WASHED SAND THEN APPROACH 100 SAND EQUIVALENT WHILE FINE-LIKE MATERIALS HAVE A ZERO SAND EQUIVALENT. A TABLE IS PROVIDED OF PROPOSED SAND EQUIVALENT VALUES FOR BASES, BITUMINOUS MIXES AND CONCRETE SAND BASED UPON CALIFORNIA EXPERIENCE. THE FUNDAMENTAL SIGNIFICANCE OF VOLUMETRIC RELATIONSHIPS ARE DISCUSSED AS CONTRASTED TO THE WEIGHT PERCENTAGES WHICH ARE COMMONLY USED TO DESCRIBE THE COMPOSITION OF SOILS AND AGGREGATES PARTICULARLY WHEN APPLIED TO BITUMINOUS MIXTURES. GRAPHS ARE PRESENTED SHOWING THE DIFFERENCES IN SAND EQUIVALENT VALUES OBTAINED WHEN COMPARABLE AMOUNTS OF KAOLINITE, BENTONITE AND QUARTZ DUST ARE MIXED WITH OTTAWA SAND. TEST RESULTS ARE ILLUSTRATED WHICH SHOW THE EFFECT ON THE SAND EQUIVALENT VALUES OF PARTICULAR AGGREGATE WHEN THE NATURAL DUST IS REPLACED WITH CRUSHED ROCK DUST. THE EFFECT OF FINENESS IS GRAPHICALLY ILLUSTRATED. IT IS CONCLUDED THAT THE SAND EQUIVALENT TEST IS USEFUL IN DETECTING THE PRESENCE OF ADVERSE AMOUNTS OF CLAY IN GRANULAR BASE MATERIALS. IT MAY BE USED AS A QUICK FIELD TEST TO CONTROL THE AMOUNT OF ADVERSE CLAYS IN CONCRETE SAND. IT MAY ALSO BE USED TO LIMIT THE AMOUNT OF FINE DUST OR CLAY THAT MAY EXIST AS A COATING ON PARTICLES OF MINERAL AGGREGATE INTENDED FOR BITUMINOUS MIXTURES.

  • Supplemental Notes:
    • Vol 32, pp 238-250
  • Authors:
    • Hveem, F N
  • Publication Date: 1953

Language

  • English

Media Info

  • Monograph Title: Proceedings of the Thirty-Second Annual Meeting of the Highway Research Board, Washington, D.C., January 13-16, 1953
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00229137
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Aug 15 2004 2:38AM