THE PROPERTIES AND RECOGNITION OF DELETERIOUS CHERTS

THE GROWING NEED TO RESORT TO CHERTY AGGREGATES THAT HAVE LITTLE OR NO KNOWN SERVICE RECORD MAKES IT IMPERATIVE TO DEFINE THE PROPERTIES OF CHERT AND PREDICT ITS SERVICE RECORD IN ORDER TO ASSIGN REALISTIC PRIORITIES TO CHERT-BEARING AGGREGATE DEPOSITS. THE PRESENT STUDY WAS UNDERTAKEN TO OUTLINE THE BASIC PROPERTIES OF CHERTS THAT OCCUR IN OHIO AGGREGATES AND TO RELATE THESE PROPERTIES TO THEIR HARMFUL EFFECTS IN CONCRETE. EMPHASIS IS PLACED ON CHEMICAL AND PHYSICAL ANALYSIS RATHER THAN ROUTINE ENGINEERING TESTS. THE MAJOR ANALYSES WERE OF SOLUBILITY, PETROGRAPHY, AND ELECTRON OPTICAL PROPERTIES. CHERTS ARE TYPED, RELATED TO AGGREGATE TYPES, CORRELATED WITH DURABILITY FACTORS BY TYPE AND CHARACTERISTIC, AND DESCRIBED WITH RESPECT TO ENGINEERING TESTS. CONCLUSIONS ARE DRAWN ABOUT THE SIGNIFICANCE OF CHERT PROPERTIES FOR CONCRETE AGGREGATES, AMONG THEM THAT A PURE SILICA CHERT IS THE LEAST DELETERIOUS CHOICE FOR CONCRETE AGGREGATE UNLESS IT HAS HIGH POROSIT OR SPONGY MORPHOLOGY. RECOMMENDATIONS FOR ENGINEERING TESTS AND FURTHER RESEARCH ARE MADE.

• Supplemental Notes:
  • 201 Pp, 90 FIG, 21 TAB, 600 REF, 5 APP
• Corporate Authors:

  University of Toledo

  Toledo, OH  United States  43606
• Publication Date: 1968-11

Subject/Index Terms

• TRT Terms: Aggregates; Beneficiation; Chemical properties; Cherts; Defects; Electron microscopes; Freeze thaw tests; Frost susceptibility; Geological surveying; Highways; Petrography; Physical properties; Porosity; Solubility; Tests
• Uncontrolled Terms: Highway damage
• Old TRIS Terms: Petrographic investigations; Solubility test
• Subject Areas: Geotechnology; Highways;

Filing Info

• Accession Number: 00217846
• Record Type: Publication
• Files: TRIS
• Created Date: Dec 7 1970 12:00AM