MOISTURE AND HEAT TRANSPORT WITH PARTICULAR REFERENCE TO CONCRETE

THREE THEORIES HAVE GAINED GENERAL ACCEPTANCE IN EXPLAINING THE MOVEMENT OF MOISTURE IN POROUS MEDIA: THE DIFFUSION THEORY, THE CAPILLARY FLOW THEORY, AND THE EVAPORATION-CONDENSATION THEORY. BECAUSE A WET POROUS SOLID ACTUALLY CONSISTS OF AT LEAST THREE PHASES, THE MECHANISM OF SIMULTANEOUS MOISTURE AND HEAT TRANSPORT IS VERY COMPLEX. DURING THE CAPILLARY AND FUNICULAR STATES OF THE SYSTEM, MOISTURE MOVES PRIMARILY BY A CONVECTIVE TRANSPORT MECHANISM, AND THE RATE OF MOISTURE MOVEMENT IS RELATIVELY INSENSITIVE TO THE PROPERTIES OF THE SOLID MATRIX. IN THE PENDULAR STATE, THE EVAPORATION-CONDENSATION MECHANISM IS PREDOMINANT, AND THE RATE OF MOISTURE MIGRATION DEPENDS ON THE COMPLEXITY OF THE PORE STRUCTURE. FOR FRESH CONCRETES THE RELATED PROBLEMS ARE AUGMENTED BY THE HYDRATION REACTIONS. /AUTHOR/

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/hrr/1970/342/342-002.pdf
• Supplemental Notes:
  • Paper sponsored by Committee on Performance of Concrete--Physical Aspects and presented at the 49th Annual Meeting. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Harmathy, T Z
• Conference:
  • 49th Annual Meeting of the Highway Research Board
  • Location: Washington District of Columbia, United States
  • Date: 1970-1-12 to 1970-1-16
• Publication Date: 1970

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 5-16
• Monograph Title: Environmental effects on concrete
• Serial:
  • Highway Research Record
  • Issue Number: 342
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Capillarity; Condensation; Convection (Fluid mechanics); Diffusion (Optics); Evaporation; Heat; Hydration; Moisture content; Motion; Porosity; Solids; Theory; Transportation
• Old TRIS Terms: Heats /energies/; Phase
• Subject Areas: Materials; Transportation (General);

Filing Info

• Accession Number: 00213916
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Jul 25 1971 12:00AM