Handbook on Concrete Block Paving (eBook)

Preface 5
Acknowledgements 6
Contents 8
List of Figures 11
List of Tables 14
1 Introduction 15
1.1 Why We Need Concrete Block Paving 15
1.2 Historical Background 15
1.3 Applications of the Concrete Block Paving 16
1.4 Advantages of Concrete Block Paving 21
1.5 Limitations 22
2 Structural Behaviour of Concrete Block Paving 23
2.1 Interlocking Mechanism 23
2.2 Shape of the Block 24
2.2.1 Field Performance of Block Shapes 25
2.3 Thickness of the Block 28
2.4 Block Size 29
2.5 Block Strength 29
2.6 Laying Pattern 30
2.7 Determination of an Effective Laying Pattern 30
2.8 Field Performance of Laying Pattern 33
2.9 Joint Between the Blocks, and Filling of Block Joints 37
3 Construction Process 41
3.1 Mix Design of ICBP 41
3.2 Factors Governing the Mix Design 42
3.2.1 Strength 42
3.2.2 Water Content 43
3.2.3 Surface Texture of the Blocks 43
3.3 Mixture Design Methods 43
3.3.1 Trial and Error Method 43
3.3.2 ACI Method 43
3.3.3 DOE Method 44
3.3.4 Particle Optimization Method 44
3.4 Problems Faced by the Industry Related to Mix Designs 44
3.4.1 Improper Aggregate Gradations 45
3.4.2 Water/Cement Ratio 46
3.4.3 Improper Curing Methods 46
3.5 A New Mixture Design Method for the ICBP Using Packing Optimization 46
3.5.1 Step 1—Tests on Aggregates 47
3.5.2 Step 2—Selection of Vibration Frequency 48
3.5.3 Step 3—Determination of Packing Density (Model Application) 48
3.5.4 Step 4—Water/Cement Ratio Calculation 49
3.5.5 Step 5—Strength Class Determination (Excessive Cement Paste) 50
3.5.6 Step 6—Calculation of Mixture Proportions 51
3.6 Summary of the Mix Design 51
3.7 Case Study 52
3.8 Advantages and Limitations of the Proposed Method 52
4 Concrete Block Pavement Design 55
4.1 Pavement Design Method for CBP 55
4.1.1 Development of Design Charts 55
4.1.2 Design Chart I (Base Improvement with 150 mm ABC Layer) 57
4.1.3 Design Chart II (Base Improvements Without Sub Base Layer) 57
4.2 Optimum Support Condition for Low Volume Roads 58
4.3 Proposed Design for Low Volume Roads 63
5 Good Practices in Concrete Block Laying 64
5.1 Design of Block Laying at Curves 64
5.2 Changes in Direction at Intersections and Corners 64
5.3 Establishing the Laying Pattern 67
5.3.1 Angle Laying (Block Axis Is Not Parallel to the Edge Restrain) 68
5.3.2 Block Axis Is Parallel to the Edge Restrain 68
6 Maintenance of Concrete Block Pavement 71
6.1 Failure Categories 72
6.1.1 Spalled Block Paving 72
6.1.2 Failure Due to the Loss of Interlocking 72
6.1.3 Failure Due to Jointing Sand Being Washed or Vibrated into the Bedding Course 73
6.1.4 Larger Gaps (Non-uniform) Between Interlocking Blocks 74
6.1.5 Sand Patches on the CBP Surface 75
6.1.6 Washing Out of Blocks 76
6.1.7 Insufficient Strength of Interlocking Blocks 78
6.1.8 Lack of Edge Restraints 79
6.1.9 Poor Support from the Base Layer 79
6.1.10 Faulting of Blocks 82
6.1.11 Rigid Joints (Mixing Concrete on Road Surface) 82
6.2 Maintenance Procedure 83
6.2.1 Removal of the Paving Blocks 83
6.3 Repair or Reinstate the Lower Pavement Layers 84
6.4 Select Replacement Blocks 85
6.5 Laying of Blocks 87
6.5.1 Selection of an Effective Laying Angle 87
6.5.2 Procedure of Laying Blocks 88
6.6 Check Joint Width and Block Heights 89
6.7 Fill Block Joint 90
6.8 Final Check 91
Appendix A: Equivalent Design Method 92
Appendix B: Subgrade Improvement for Medium Traffic Level 94
Appendix C: Design Specifications 95
Appendix D: Edge Restraints 96
References 102