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Guide to Concrete Repair Second Edition

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Guide to Concrete Repair Second Edition ON r in the West August 2015 Guide to Concrete Repair Second Edition Prepared by: Kurt F. von Fay, Civil Engineer Concrete, Geotechnical, and Structural Laboratory U.S. Department of the Interior Bureau of Reclamation Technical Service Center August 2015 Mission Statements The U.S. Department of the Interior protects America’s natural resources and heritage, honors our cultures and tribal communities, and supplies the energy to power our future. The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. Acknowledgments Acknowledgment is due the original author of this guide, W. Glenn Smoak, for all his efforts to prepare the first edition. For this edition, many people were involved in conducting research and field work, which provided valuable information for this update, and their contributions and hard work are greatly appreciated. They include Kurt D. Mitchell, Richard Pepin, Gregg Day, Jim Bowen, Dr. Alexander Vaysburd, Dr. Benoit Bissonnette, Maxim Morency, Brandon Poos, Westin Joy, David (Warren) Starbuck, Dr. Matthew Klein, and John (Bret) Robertson. Dr. William F. Kepler obtained much of the funding to prepare this updated guide. Nancy Arthur worked extensively on reviewing and editing the guide specifications sections and was a great help making sure they said what I meant to say. Teri Manross deserves recognition for the numerous hours she put into reviewing, editing and formatting this Guide. The assistance of these and numerous others is gratefully acknowledged. Contents PART I: RECLAMATION'S METHODOLOGY FOR CONCRETE MAINTENANCE AND REPAIR Page A. Repair and Maintenance of Concrete 1. Introduction .......................................................................................... I-1 a. Concrete Repair and Maintenance System ................................... I-2 2. Maintenance of Concrete ...................................................................... I-3 3. General Requirements for Quality Repair ............................................ I-8 a. Workmanship ................................................................................ I-9 b. Procedures ..................................................................................... I-9 c. Materials ..................................................................................... I-10 B. Using Reclamation's Concrete Maintenance and Repair System 1. Determine the Cause(s) of Damage .................................................... I-13 2. Evaluate the Extent of Damage .......................................................... I-16 3. Evaluate the Need to Repair ............................................................... I-19 4. Select the Repair Method and Material .............................................. I-25 5. Prepare the Existing Concrete for Repair ........................................... I-26 a. Saw Cut Perimeters ..................................................................... I-26 b. Concrete Removal ....................................................................... I-29 c. Reinforcing Steel Preparation ..................................................... I-34 d. Primary Cleaning ........................................................................ I-36 e. Protecting the Prepared Area ...................................................... I-37 f. Secondary Cleaning .................................................................... I-37 6. Apply the Repair Method ................................................................... I-39 7. Cure the Repair Properly .................................................................... I-39 C. Causes of Damage to Concrete 1. Excess Concrete Mix Water ............................................................... I-41 2. Faulty Design ..................................................................................... I-43 3. Construction Defects .......................................................................... I-48 4. Sulfate Deterioration .......................................................................... I-51 5. Alkali-Aggregate Reaction ................................................................. I-52 6. Deterioration Caused by Cyclic Freezing and Thawing Weather ...... I-56 7. Abrasion-Erosion Damage ................................................................. I-60 8. Cavitation Damage ............................................................................. I-65 9. Corrosion of Reinforcing Steel ........................................................... I-68 i Contents (continued) Page 10. Acid Exposure .................................................................................... I-70 11. Cracking ............................................................................................ I-72 12. Structural Overloads ........................................................................... I-81 13. Multiple Causes of Damage ............................................................... I-83 D. Standard Methods of Concrete Repair 1. Sealers and Coatings .......................................................................... I-88 a. High Molecular Weight Methacrylic Sealing Compounds ......... I-90 (1) Preparation ......................................................................... I-91 (2) Materials ............................................................................ I-92 (3) Application ......................................................................... I-92 (4) Curing and Protection ........................................................ I-93 b. Low Viscosity Epoxy Sealing Compounds ................................ I-93 (1) Preparation ......................................................................... I-94 (2) Materials ........................................................................... I-95 (3) Application ......................................................................... I-96 (4) Curing and Protection ........................................................ I-96 c. Silane and Siloxane Sealing Compound ..................................... I-96 (1) Preparation ......................................................................... I-97 (2) Materials ............................................................................ I-97 (3) Application ......................................................................... I-98 (4) Curing ................................................................................ I-99 d. Coating Compounds for Concrete .............................................. I-99 (1) Preparation ....................................................................... I-100 (2) Application ....................................................................... I-102 (3) Curing .............................................................................. I-103 2. Thin Repairs ..................................................................................... I-103 a. Surface Grinding ....................................................................... I-104 b. Portland Cement Mortar ........................................................... I-105 (1) Preparation ....................................................................... I-106 (2) Materials .......................................................................... I-107 (3) Application ....................................................................... I-107 (4) Curing .............................................................................. I-108 c. Dry Pack and Bonded Dry Pack ............................................... I-108 (1) Preparation ....................................................................... I-109 (a) Method 1 .................................................................... I-110 (b) Method 2 ................................................................... I-110 (c) Method 3 .................................................................... I-110 (2) Materials .......................................................................... I-111 ii Contents (continued) Page (3) Application ....................................................................... I-111 (4) Curing and Protection ...................................................... I-112 d. Polymer Concrete, Including Epoxy Mortar ............................. I-112 (1) Preparation ....................................................................... I-114 (2) Materials ......................................................................... I-115 (3) Mixing and Handling ...................................................... I-116 (4) Application ....................................................................... I-118 (5) Curing .............................................................................. I-120 (6) Storage ............................................................................ I-121 e. Epoxy-Bonded Replacement Concrete ..................................... I-121 (1) Preparation ....................................................................... I-122 (2) Materials .......................................................................... I-122 (3) Application ....................................................................... I-123 (4) Curing .............................................................................. I-124 f. Packaged Cementitious and Chemical Repair Mortars ...........
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