THE CAPILLARY SIZE RESTRICTIONS ON ICE FORMATION IN HARDENED PORTLAND CEMENT PASTES

IT IS PROPOSED THAT INITIAL ICE FORMATION IN SUPERCOOLED WATER IN THE CAPILLARIES OCCURS DENDRITICALLY, JUST AS IT DOES IN BULK WATER, THROUGH ONLY THOSE SUFFICIENTLY LARGE CAPILLARIES WHICH ARE CONTIGUOUS WITH THE INITIALLY SEEDED CAPILLARIES. SUBSEQUENT GROWTH OF THIS DENDRITIC NETWORK OF ICE CRYSTALS AND RESULTING EXPANSIONS DURING COOLING DEPEND PRIMARILY ON FREEZING IN SMALLER CAPILLARIES AT LOWER TEMPERATURES. THIS THEORY IS SUPPORTED BY THE RESULTS OF EXPERIMENTS IN WHICH FREEZING PROPAGATION RATES AND TEMPERATURE RISES WERE MEASURED DURING TESTS WITH SUPERCOOLED PASTES, AND BY EXPERIMENTS IN WHICH DIMENSIONAL CHANGES WERE MEASURED DURING COOLING AND WARMING THROUGH FREEZING TEMPERATURES. /PCA/

• Authors:
  • Helmuth, R A
• Publication Date: 0

Media Info

• Serial:
  • Portland Cement Assoc R & D Lab Bull
  • Issue Number: 0

Subject/Index Terms

• TRT Terms: Capillaries; Freezing; Hardness; Icing; Pastes; Portland cement; Volume changes
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213596
• Record Type: Publication
• Source Agency: Portland Cement Association
• Report/Paper Numbers: No 156
• Files: TRIS
• Created Date: Jun 1 1970 12:00AM