ACCELERATED ALKALI-SILICA REACTIVITY TESTING OF RECYCLED CONCRETE PAVEMENT

Techniques and procedures are investigated for assessing the alkali-silica reactivity (ASR) expansion potential of concrete that was made from recycled concrete aggregate, was known to have ASR, or was capable of ASR under conditions of increased alkalinity. Laboratory tests included evaluating prisms characterized by variable surface-to-volume ratios, increased temperature, microwave energy, increased alkali content, and ultrasonic energy. Standard 280-mm (11-in.) prisms with 76.2-mm (3-in.) faces, which were cast with four 6.35-mm (0.5-in.) parallel longitudinal holes, were shown to accelerate ASR and to lower the coefficient of variation of the expansion data. The expansions of 76.2-mm (3-in.) concrete cubes were found to be greatly accelerated, compared with standard prisms. Concrete prisms were subjected to AASHTO T303 and ASTM 1293 conditions and were compared to modified versions of the same tests. Modified AASHTO T303 and modified ASTM 1293 conditions were found to effectively accelerate ASR in concrete prisms cast with holes. Prisms that were sealed in evacuated plastic bags with water were found to effectively accelerate ASR expansion. Testing to date has eliminated the use of ultrasonic energy because it was shown to have no effect on ASR acceleration.

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 1-8
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00796887
  • Record Type: Publication
  • ISBN: 030906676X
  • Files: TRIS, TRB, ATRI
  • Created Date: Aug 3 2000 12:00AM