SYNTHETIC AGGREGATES CAN SERVE EFFECTIVELY IN MODERN HIGHWAYS

RESEARCH STUDIES ARE REPORTED INVOLVING THE USES OF SYNTHETIC AGGREGATES IN SUCH HIGHWAY APPLICATIONS AS BITUMINOUS PAVEMENTS, CONCRETE PAVEMENTS, CONCRETE BRIDGES AND BASE MATERIALS. A RESEARCH-SIZED ROTARY KILN IN WHICH SYNTHETIC AGGREGATES ARE MANUFACTURED IN SMALL QUANTITIES AND STUDIED IN THE LABORATORY TO DETERMINE THEIR QUALITY FOR ENGINEERING CONSTRUCTION IS BEING USED. RAW MATERIALS, DUG UP IN ABUNDANCE IN MANY AREAS, ARE INTRODUCED BY MEANS OF A CONVEYOR INTO A ROTARY KILN. THE KILN, WHICH IS CAPABLE OF HEATING THE MATERIAL TO TEMPERATURES IN EXCESS OF 2000 F, TRANSFORMS THE RAW MATERIAL INTO A FUSED SILICATE, OR WHAT IS ESSENTIALLY A LOW GRADE GLASS. THE END PRODUCT IS SYNTHETIC AGGREGATE AND IS HARD, DURABLE AND STRONG. FREEZE- THAW STUDIES REVEALED THAT THE AGGREGATE ABSORPTION FACTOR OF THE SYNTHETIC, LIGHT-WEIGHT COARSE AGGREGATES STUDIED IS A READILY OBTAINABLE PROPERTY WHICH CAN BE USED TO PREDICT THE COARSE AGGREGATES RESISTANCE TO FREEZING AND THAWING AND THE RESULTING CONCRETE'S DURABILITY AGAINST THESE PHYSICAL PHENOMENA. CONCRETE SPECIMENS MADE WITH SELECTED SYNTHETIC COARSE, LIGHTWEIGHT AGGREGATES SUBJECTED TO FREEZING IN AIR AND THAWING IN WATER REVEALED THAT THE DEGREE OF AGGREGATE PRE-WETTING HAD A DEFINITE EFFECT ON THE FREEZE-THAW DURABILITY OF THE CONCRETES TESTED. THE LIGHT-WEIGHT AGGREGATE SERVING AS COVERSTONE FOR SEAL COATS AND SURFACE TREATMENTS HAS PROVED SUCCESSFUL. PRESENT RESEARCH AND FIELD TRIALS INDICATE THAT HIGH QUALITY HOT-MIX CAN BE PRODUCED USING LARGE QUANTITIES OF SYNTHETIC AGGREGATES. SUITABLE MIXES HAVE BEEN DESIGNED AND PRODUCED FOR SURFACE COARSE, BASE AND PATCHING AND SOME OF THESE DESIGNS HAVE EXCELLENT SERVICE RECORDS FOR FIVE YEARS OR MORE. SYNTHETIC AGGREGATES USED IN SEALS AND SURFACE COARSE DESIGNS OFFER COLOR DYNAMICS FOR TRAFFIC ENGINEERING. BY PROPER SELECTION OF RAW MATERIALS AND CONTROLLED BURNING TECHNIQUES, SPECIFIC AND HIGHLY STABLE COLORS MAY BE PRODUCED. COLORED SYNTHETIC AGGREGATES APPEARS TO OFFER A SOLUTION TO COLORED PAVEMENTS. IT IS CONCLUDED THAT THERE IS OVERALL POTENTIAL OF USES FOR SYNTHETIC AGGREGATE IN CONCRETE FOR BUILDINGS, SPECIAL STRUCTURES, BRIDGES AND PAVEMENTS, INCLUDING ASPHALTIC APPLICATIONS AS COVERSTONE AND THE STRUCTURAL INGREDIENT IN SEAL COATS AND HOT MIXES, AS WELL AS IN HIGHWAY BASES.

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  • Supplemental Notes:
    • Vol 98, No 11, PP 93-95, 3 PHOT, 4 REF
  • Authors:
    • Horn, L J
  • Publication Date: 1967-11

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  • Accession Number: 00210733
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 17 1994 12:00AM