CONTENTS List of figures iv List of tables iv Foreword v 1 Introduction 1 1.1Overview of BS EN 1504 1 1.2 Scope and structure of this report Deterioration processes 2 2.1Background 4 2.2 Design and construction defects 5 2.3 Corrosion of steel in concrete resulting from carbonation and chlorides 5 2.4 The principles of repairing and controlling corrosion 9 2.5 Concrete degradation 10 2.6 Environmental influences 12 2.7 Structural damage 13 3.Repair of concrete 15 3.1Introduction 15 3.2 Arresting degradation 16 3.3 Minimum requirements before work begins 16 3.4 Treating exposed steel 18 3.5 Filling holes 18 3.6 Preventing further degradation 19 3.7 Strengthening of weakened structures 19 4. General principles (Part 9) 20 4.1Scope of Part 9 20 4.2 Overview 20 4.3 Application, product testing and CE marking 22 5. Surface protection systems 23 5.1 Surface treatments for concrete 23 5.2 Surface protection systems 24 6. Repair mortars, structural bonding and reinforcement protection 27 6.1 Repair mortars 27 6.2 Structural bonding 29 6.3 Reinforcement protection 30 7. Concrete injection 31 7.1 Introduction 31 7.2Design considerations 32 7.3 Scope 33 7.4 Terms and definitions 34 7.5Performance characteristics 34 7.6 Annexes 35 8. Anchoring of reinforcing steel 36 8.1Application 36 8.2 Design considerations 36 8.3 Terms and definitions 36 8.4 Performance characteristics and requirements 37 8.5 Installation requirements 37 9. Achieving successful repairs 40 9.1 Content 40 9.2 Implementing the sections 40 10. Performance-based rehabilitation of reinforced concrete structures 43 10.1 The CONREPNET project 43 10.2 Lessons learnt from past repairs and current industry practices 43 10.3 A look to the future 46 10. 4 Summary 48 11. Assessment of structures and ongoing monitoring of concrete repairs 49 11.1 Records 49 11.2 Concrete repair management 49 11.3 Testing 50 11.4 Assessment 51 11.5 Routine maintenance 51 References 53 Appendix A. Case studies illustrating the application of BS EN 1504 56 A1 Mayorhold multi-storey car park 56 A1.1 Description of the structure 56 A1.2 Problems that prompted repair 57 A1.3 Inspection and evaluation methods 58 A1.4 Repair and protection system selection 59 A1.5 Preview of corrosion management scheme 60 A1.6 Project installation and compliance with BS EN 1504 Part 9 60 A1.7 Special features 62 A2 University campus structures 63 A2.1 The structures 63 A2.2The condition and situation of the structures 63 A2.3 Applying the Principles of BS EN 1504 to the rehabilitation process 65 A2.4 Design and specification of the work 66 A2.5 Site tests 67 A2.6Conclusions 68 Appendix B. CE marking 60 Appendix C. Standards relevant to protection and repair of concrete land standard test methods for BS EN 1504 Parts 2 to 7 71