ACI 408R 03 2003
$60.40
408R-03: Bond and Development of Straight Reinforcing Bars in Tension (Reapproved 2012)
| Published By | Publication Date | Number of Pages |
| ACI | 2003 | 49 |
The performance of reinforced concrete structures depends on adequate bond strength between concrete and reinforcing steel. This report describes bond and development of straight reinforcing bars under tensile load. Bond behavior and the factors affecting bond are discussed, including concrete cover and bar spacing, bar size, transverse reinforcement, bar geometry, concrete properties, steel stress and yield strength, bar surface condition, bar casting position, development and splice length, distance between spliced bars, and concrete consolidation. Descriptive equations and design provisions for development and splice strength are presented and compared using a large database of test results. The contents of the database are summarized, and a protocol for bond tests is presented. Test data and reliability analyses demonstrate that, for compressive strengths up to at least 16,000 psi (110 MPa), the contribution of concrete strength to bond is best represented by the compressive strength to the 1/4 power, while the contribution of concrete to the added bond strength provided by transverse reinforcement is best represented by compressive strength to a power between 3/4 and 1.0. The lower value is used in proposed design equations. These values are in contrast with the square root of compressive strength, which normally is used in both descriptive and design expressions. Provisions for bond in ACI 318-02 are shown to be unconservative in some instances; specifically, the 0.8 bar size factor for smaller bars should not be used and a f-factor for bond is needed to provide a consistent level of reliability against bond failure. Descriptive equations and design procedures developed by Committee 408 that provide improved levels of reliability, safety, and economy are presented. The ACI Committee 408 design procedures do not require the use of the 1.3 factor for Class B splices that is required by ACI 318. Keywords: anchorage; bond; concrete; deformed reinforcement; development length; reinforced concrete; reinforcement; relative rib area; splice; stirrup; tie.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 1 | CONTENTS CONTENTS |
| 2 | PREFACE PREFACE |
| 3 | CHAPTER 1— BOND BEHAVIOR CHAPTER 1— BOND BEHAVIOR |
| 4 | 1.1—Bond forces—background 1.1—Bond forces—background |
| 6 | 1.2—Test specimens 1.2—Test specimens 1.3—Details of bond response 1.3—Details of bond response |
| 8 | 1.4—Notation 1.4—Notation |
| 9 | CHAPTER 2— FACTORS AFFECTING BOND CHAPTER 2— FACTORS AFFECTING BOND 2.1—Structural characteristics 2.1—Structural characteristics 2.1.1 Concrete cover and bar spacing 2.1.1 Concrete cover and bar spacing |
| 10 | 2.1.2 Development and splice length 2.1.2 Development and splice length 2.1.3 Transverse reinforcement 2.1.3 Transverse reinforcement |
| 12 | 2.1.4 Bar casting position 2.1.4 Bar casting position |
| 13 | 2.1.5 Noncontact lap splices 2.1.5 Noncontact lap splices |
| 15 | 2.2—Bar properties 2.2—Bar properties 2.2.1 Bar size 2.2.1 Bar size 2.2.2 Bar geometry 2.2.2 Bar geometry |
| 17 | 2.2.3 Steel stress and yield strength 2.2.3 Steel stress and yield strength 2.2.4 Bar surface condition 2.2.4 Bar surface condition 2.2.4.1 Bar cleanliness 2.2.4.1 Bar cleanliness 2.2.4.2 Epoxy-coated bars 2.2.4.2 Epoxy-coated bars |
| 18 | 2.3—Concrete properties 2.3—Concrete properties 2.3.1 Compressive strength 2.3.1 Compressive strength |
| 19 | 2.3.2 Aggregate type and quantity 2.3.2 Aggregate type and quantity 2.3.3 Tensile strength and fracture energy 2.3.3 Tensile strength and fracture energy |
| 20 | 2.3.4 Lightweight concrete 2.3.4 Lightweight concrete |
| 21 | 2.3.5 Concrete slump and workability admixtures 2.3.5 Concrete slump and workability admixtures |
| 22 | 2.3.6 Mineral admixtures 2.3.6 Mineral admixtures 2.3.7 Fiber reinforcement 2.3.7 Fiber reinforcement |
| 23 | 2.3.8 Consolidation 2.3.8 Consolidation 2.3.8.1 Vibration 2.3.8.1 Vibration |
| 24 | 2.3.8.2 Construction-related vibrations 2.3.8.2 Construction-related vibrations |
| 25 | 2.3.8.3 Revibration 2.3.8.3 Revibration 2.4—Summary 2.4—Summary CHAPTER 3— DESCRIPTIVE EQUATIONS CHAPTER 3— DESCRIPTIVE EQUATIONS 3.1—Orangun, Jirsa, and Breen 3.1—Orangun, Jirsa, and Breen |
| 26 | 3.2—Darwin et al. 3.2—Darwin et al. |
| 27 | 3.3—Zuo and Darwin 3.3—Zuo and Darwin 3.4—Esfahani and Rangan 3.4—Esfahani and Rangan 3.5—ACI Committee 408 3.5—ACI Committee 408 3.6—Comparisons 3.6—Comparisons |
| 29 | CHAPTER 4— DESIGN PROVISIONS CHAPTER 4— DESIGN PROVISIONS 4.1—ACI 318 4.1—ACI 318 |
| 30 | 4.2—ACI 408.3 4.2—ACI 408.3 |
| 31 | 4.3—Recommendations by ACI Committee 408 4.3—Recommendations by ACI Committee 408 4.3.1 4.3.1 |
| 32 | 4.4—CEB-FIP Model Code 4.4—CEB-FIP Model Code |
| 33 | 4.5—Structural reliability and comparison of design expressions 4.5—Structural reliability and comparison of design expressions 4.5.1 Comparison with data 4.5.1 Comparison with data |
| 34 | 4.5.2 g-factor in ACI 318 4.5.2 g-factor in ACI 318 4.5.3 Reliability—ACI 318 and ACI 408R 4.5.3 Reliability—ACI 318 and ACI 408R |
| 36 | 4.5.4 Comparisons of development and splice lengthsACI 318, ACI 408.3, and ACI 408 4.5.4 Comparisons of development and splice lengthsACI 318, ACI 408.3, and ACI 408 |
| 38 | CHAPTER 5— DATABASE CHAPTER 5— DATABASE 5.1—Bar stresses 5.1—Bar stresses |
| 39 | 5.2—Database 5.2—Database CHAPTER 6— TEST PROTOCOL CHAPTER 6— TEST PROTOCOL 6.1—Reported properties of reinforcement concrete stress for values of compressive strength 3000 psi (20.7 MPa) 6.1—Reported properties of reinforcement concrete stress for values of compressive strength 3000 psi (20.7 MPa) |
| 40 | 6.2—Concrete properties 6.2—Concrete properties 6.3—Specimen properties 6.3—Specimen properties 6.4—Details of test 6.4—Details of test 6.5—Analysis method 6.5—Analysis method |
| 41 | 6.6—Relative rib area 6.6—Relative rib area 6.6.1 Measuring deformation height 6.6.1 Measuring deformation height CHAPTER 7— REFERENCES CHAPTER 7— REFERENCES 7.1 — Referenced standards and reports 7.1 — Referenced standards and reports |
| 42 | 7.2—Cited references 7.2—Cited references |
| 47 | APPENDIX A—SI EQUATIONS APPENDIX A—SI EQUATIONS |
