EPOXY RESIN CURE EVALUATION: DATA REPORT

THERE IS A GROWING REQUIREMENT TO LOCATE BOTH SHALLOW AND DEEP UNDERGROUND PROTECTIVE STRUCTURES IN NATURAL ROCK FORMATIONS. THE DEVELOPMENT OF IMPROVED METHODS AND MATERIALS FOR EFFECTIVELY INCREASING THE SHEAR AND TENSILE STRENGTH OF FRACTURED OR WEAKENED ROCK ZONES SURROUNDING THE OPENINGS WOULD AID IN REDUCING OR ELIMINATING THE LINEAR REQUIREMENTS. THESE METHODS MAY TAKE THE FORM OF GROUTING, ROCK BOLTING, OR A COMBINATION OF BOTH. AN EARLIER PLACEMENT AT THE NORTH AMERICAN AIR DEFENSE COMMAND, EMPLOYING AN EPOXY RESIN, SUGGESTED THE FEASIBILITY OF UTILIZING EPOXY RESINS FOR STABILIZING FRACTURED ROCK MASSES. HOWEVER, THE EFFECTS OF IN SITU ROCK CONDITIONS UPON THE ENGINEERING PROPERTIES OF AN EPOXY RESIN SYSTEM REMAINED QUESTIONABLE. SPECIFICALLY, THE EFFECT OF UNCONTROLLED TEMPERATURE, RELATIVE HUMIDITY, AND TIME OF CURE, RESULTING FROM FIELD PLACEMENTS, ON THE INHERENT TENSILE STRENGTH OF THE CHEMICAL ADHESIVES REMAINS UNKNOWN. IN THIS STUDY, THE EFFECT OF VARIOUS TEMPERATURES AND TIMES OF CURE AT SELECTED VALUES OF RELATIVE HUMIDITY ON THE TENSILE PROPERTIES OF A SPECIFIC EPOXY RESIN SYSTEM WERE EVALUATED IN THE LABORATORY. THE STANDARD ASTM D 638 TENSION STRENGTH TEST WAS USED. THE TEMPERATURES OF CURE RANGED FROM 38 F TO 100 F. THE RELATIVE HUMIDITIES RANGED FROM 30% TO 100% (SATURATED). THESE TEMPERATURES WERE CHOSEN TO REPRESENT LABORATORY DATA FOR A WIDE RANGE OF ANTICIPATED FIELD CONDITIONS. THE TIME OF CURE RANGED FROM 30 TO 180 DAYS WITH TESTS AT 30-DAY INCREMENTS. THE APPARENT EFFECT OF RELATIVE HUMIDITY WAS UNANTICIPATED AND HENCE, NO QUANTITATIVE TRENDS WERE ESTABLISHED. HOWEVER, THE LABORATORY DATA SUGGESTED THAT THE ENGINEERING PROPERTIES OF THE EPOXY RESIN SYSTEM WERE SENSITIVE TO TIME AND TEMPERATURE OF CURE AS WELL AS RELATIVE HUMIDITY. IF THIS HOLDS FOR OTHER EPOXY RESIN SYSTEMS USED IN FIELD PLACEMENTS, SOME ASSESSMENT OF TENSILE PROPERTIES SHOULD BE REQUIRED TO ANTICIPATE FIELD CONDITIONS AND INSURE ADEQUATE PERFORMANCE. IN THIS SERIES OF TESTS, THE EPOXY RESIN SYSTEM PERFORMED WELL FOR ENVIRONMENTAL TEMPERATURES IN THE RANGE OF 50 F, 80 F WITH THE RELATIVE HUMIDITY NOT EXCEEDING 75%. /AUTHOR/

• Supplemental Notes:
  • Tech Rept M-5, 6 PP, 1 FIG, 2 TAB, 4 PHOT, 4 REFS
• Corporate Authors:

  Construction Engineering Research Laboratory

  Army Corps of Engineers, P.O. Box 4005
  Champaign, IL  United States  61820
• Publication Date: 1971-2

Subject/Index Terms

• TRT Terms: Concrete curing; Epoxy resins; Grouting; Humidity; Rockbolts; Temperature; Tensile strength; Time
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00217078
• Record Type: Publication
• Files: TRIS
• Created Date: May 10 1971 12:00AM