Prestessing Manual
STATE OF CALIFORNIA DEPARTMENT OF TRANSPORTATION ENGINEERING SERVICES
PRESTRESS MANUAL
A GUIDE FOR FIELD INSPECTION OF CAST-IN-PLACE POST-TENSIONED STRUCTURES
JANUARY 2005
Revision 1 05/05
TABLE OF CONTENTS Topic INTRODUCTION SAFETY PRESTRESS WORKING DRAWINGS PRESTRESSING DUCTS PRESTRESSING STRANDS/BARS ANCHORAGE DEVICES STRAND WEDGES PRESTRESSING JACKS PRESTRESSING OPERATION a. b. c. d. Preparation for Stressing Inspection Field Inspection Overstressing of Prestressing Steel Elongation Measurements and Calculations Page 1 2 3 5 8 15 16 17 20 20 21 27 28 30 35 35 36 42 42 43 51 57 64 74
GROUTING OPERATION APPENDIX A – PRESTRESSING SYSTEMS a. b. c. d. New System Proposals Presently Used Systems Soil Anchors Girder Strengthening
APPENDIX B – PRESSURE CELL APPENDIX C – INSPECTION CHECKLIST APPENDIX D – POST-TENSIONING LOSSES AND ELONGATIONS APPENDIX E – EXAMPLE CALCULATIONS APPENDIX F – CALIFORNIA TEST # 541 (FLOW CONE METHOD)
California Prestressing Manual
INTRODUCTION
January 2005
A large percentage of the bridges built in California are prestressed, post-tensioned type structures. As a bridge engineer working for the Divisions of Structure Construction, you should understand the construction principles relating to prestressed, post-tensioned bridge construction. This Prestress Manual has been compiled to provide the field engineer with the necessary information and the background to perform three basic duties: 1. 2. 3. Check the contractor’s working drawings. Provide thorough and complete inspection during the construction of the bridge with respect to the prestressing operation. Understand and enforce Section 50 titled “Prestressing Concrete” of the Standard Specifications and any pertinent references. The information included herein is to be considered as both a reference and guideline for structure representatives and assistant structure representatives. This manual should be reviewed both prior to working drawing review and during
PRESTRESS MANUAL
A GUIDE FOR FIELD INSPECTION OF CAST-IN-PLACE POST-TENSIONED STRUCTURES
JANUARY 2005
Revision 1 05/05
TABLE OF CONTENTS Topic INTRODUCTION SAFETY PRESTRESS WORKING DRAWINGS PRESTRESSING DUCTS PRESTRESSING STRANDS/BARS ANCHORAGE DEVICES STRAND WEDGES PRESTRESSING JACKS PRESTRESSING OPERATION a. b. c. d. Preparation for Stressing Inspection Field Inspection Overstressing of Prestressing Steel Elongation Measurements and Calculations Page 1 2 3 5 8 15 16 17 20 20 21 27 28 30 35 35 36 42 42 43 51 57 64 74
GROUTING OPERATION APPENDIX A – PRESTRESSING SYSTEMS a. b. c. d. New System Proposals Presently Used Systems Soil Anchors Girder Strengthening
APPENDIX B – PRESSURE CELL APPENDIX C – INSPECTION CHECKLIST APPENDIX D – POST-TENSIONING LOSSES AND ELONGATIONS APPENDIX E – EXAMPLE CALCULATIONS APPENDIX F – CALIFORNIA TEST # 541 (FLOW CONE METHOD)
California Prestressing Manual
INTRODUCTION
January 2005
A large percentage of the bridges built in California are prestressed, post-tensioned type structures. As a bridge engineer working for the Divisions of Structure Construction, you should understand the construction principles relating to prestressed, post-tensioned bridge construction. This Prestress Manual has been compiled to provide the field engineer with the necessary information and the background to perform three basic duties: 1. 2. 3. Check the contractor’s working drawings. Provide thorough and complete inspection during the construction of the bridge with respect to the prestressing operation. Understand and enforce Section 50 titled “Prestressing Concrete” of the Standard Specifications and any pertinent references. The information included herein is to be considered as both a reference and guideline for structure representatives and assistant structure representatives. This manual should be reviewed both prior to working drawing review and during