1st Edition

Cold Weather Concreting

By B.A. Krylov Copyright 1997

    Concreting in cold weather requires special knowledge and skills to ensure accelerated hardening and high quality in plain- and reinforced-concrete structures. Cold Weather Concreting familiarizes concrete specialists with the characteristic features of concrete in cold weather, including the effects of frost, methods for hardening in subzero temperatures, and other challenges in cold-weather concreting. Both practical techniques and their underlying theories are covered.
    The book presents many methods for the thermal treatment of concrete by means of electric current--information previously available only in the Russian literature. It presents unique data in the form of diagrams, drawings, and tables, including a chart of the phase state of concretes of different strengths in the process of freezing at different temperatures, the variation of concrete strains in freezing and thawing, and a diagram of electric fields in concrete when electrodes are placed in front of stirrups.

    1. Winter Construction
    Specific Features of Winter
    Concreting in Winter Conditions
    Problems of Winter Concreting
    2. Effects of Frost on the Structure and Properties of Concrete
    Modern Views on the Hardening of Concrete
    The Phase State of Water in Concrete at Different Temperatures
    The Mechanism of Deterioration of Concrete Due to Early Freezing
    Precuring of Concrete Before Freezing
    Effects of Early Freezing on Concrete Properties
    Concrete in the Frozen State and its Basic Properties
    3. Preparations for Concreting in Winter Conditions
    4. Concretes Containing Antifreeze Admixtures
    The Principle of the Method and its Theory
    Selection and Assignment of Antifreeze Admixtures
    Procedures
    5. Thermos Curing
    The Principle and Application of the Thermos Method
    Placement and Curing of Concrete in Structures Built on Permafrost Ground
    Curing and Cooling of Concrete in Massive Structures
    6. Electric Contact Heating of Concrete
    The Principle and Application of the Method
    Heaters for Electric Contact Heating
    Heating Formworks Covered with Conductive Materials
    Application of Electric Contact Heating of Concrete
    7. Electrode Heating of Concrete
    Electric Conductivity of Concrete
    Processes in Concrete Caused by Electric Current Passing Through it
    Electrodes for Electric Heating of Concrete
    Processes at the Interface of Concrete and an Electrode
    Electric and Thermal Fields in Electric Heating
    External Mass Exchange in Electric Heating
    Electrode Heating Procedures
    8. Electric Preheating of Concrete Mixtures
    General Considerations and the Principle of the Method
    The Theoretical Background of the Accelerated Heating of Concrete Mixtures
    Internal Heat Exchange During the Accelerated Electric Heating of Concrete
    Changes in Plastic Properties of Concrete Caused by Accelerated Heating
    Physical-Mechanical Properties of Concrete Subjected to Accelerated Heating
    Equipment for Electric Preheating of Concrete Mixtures
    Concreting Procedures with Preheated Concrete Mixtures
    Preheating of Concrete Mixtures in Truck Mixers
    9. Induction Heating of Concrete
    The Principle and Application of the Method
    Determining Basic Parameters of Heating
    Induction Heating of Concrete in Framed Structures
    10. Sealing Joints Between Precast Units and Between Precast and Cast-in-Place Members in Composite Construction
    Specific Features of Joints Between Precast Concrete Units
    Erection of Precast Concrete Units
    Curing of Sealing Concrete in Joints
    11. Curing of Cast-in-Place Concrete in Enclosures
    The Principle of the Method and Types of Enclosures
    Curing of Concrete in Enclosures
    Air Exchange in Enclosures
    Concreting in Enclosures
    12. Some Problems of Economics of Winter Concreting
    Appendix - Specific Power Values Required to Heat Concrete with Strip Electrodes Placed on One Side
    References
    Index

    Biography

    Boris Alexandrovich Krylov, born in 1926, is a doctor of engineering, professor, and academician of the Academy of Architectural and Building Sciences of Russia, of the Russian Engineering Academy, and of the International Academy of Informatization. Dr. Krylov is an expert in the field of construction under extreme conditions, including Arctic and permafrost regions and regions with dry, hot climate, and in problems relating to acceleration of concrete hardening rate at precast concrete factories and at building sites. He is the author of more than 300 publications, inventions and patents. Dr. Krylov represented the U.S.S.R. at the Reunion Internationale des laboratoires d’essais et de recherches sur les materiaux et les constructions (RILEM) for many years, heading the Technical Committee on Winter Concreting (39-BH) in this organization. He presently is Deputy Director for Research of the Research Institute of Concrete and Reinforced Concrete in Moscow and a professor at Moscow State University of Construction.