Description
Bendable concrete, also known as Engineered Cementitious Composite (ECC) or Strain Hardening Cementitious Composites (SHCC), represents a revolutionary advancement in construction materials, offering exceptional durability, ductility, and flexibility. This document covers essential aspects from material specifications to structural analysis, applications, and guidelines for material selection and
processing methods.
The introductory chapter, sets the stage by defining the scope of the document, introducing ECC, clarifying terminology, and establishing units for measurement. Second chapter provides detailed specifications for ECC, including processing methods such as preparation, placement, and curing. Mechanical properties, crack width, volume stability, and durability characteristics are thoroughly explored, ensuring a comprehensive understanding of the material's performance. In the third chapter, quality control procedures are outlined to ensure consistency and reliability in ECC production. This includes testing fresh properties, conducting mechanical testing, and visual inspection to maintain quality standards. Structural analysis techniques are discussed in chapter 4, including constitutive models for monotonic and cyclic loading scenarios. This chapter provides engineers with the necessary tools to effectively design and analyze ECC structures. In chapter 5, diverse applications of bendable concrete are explored, ranging from bridges and buildings to water infrastructure and subsurface structures. The benefits of ECC, including enhanced durability and flexibility, are highlighted in various construction scenarios. The last chapter provides practical guidelines for selecting raw materials, processing approaches, and mix proportions to achieve desired ECC properties. Various mixture types are discussed, catering to different project requirements and performance criteria.
This guideline serves as a comprehensive resource for engineers, researchers, and practitioners seeking to harness the potential of bendable concrete in construction projects. By addressing key aspects of material specifications, quality control, structural analysis, and applications, it empowers stakeholders to leverage ECC effectively, fostering innovation and advancement in the construction industry.
Keywords:
NEx, Engineered Cementitious Composites, ECC, bendable concrete, fibers, resins, buildings, bridges, culverts, retaining walls, dams, water retaining structures, tunnels
Table of Contents
1. Introduction 7
1.1. Scope 7
1.2. Definition 7
1.3. Terminology 8
1.4. Units 8
Chapter 2. Material Specifications 9
2.1. General 9
2.2. Processing 10
2.2.1. Preparation 10
2.2.2. Placement 12
2.2.3. Curing 12
2.3. Mechanical properties 13
2.3.1. Tensile properties 13
2.3.2. Compressive properties 17
2.3.3. Flexural properties 17
2.3.4. Young’s modulus, Poisson’s ratio, fracture toughness, and flaw size distribution 18
2.3.5. Fatigue resistance 20
2.4. Crack width 21
2.4.1. Average and maximum crack width 23
2.4.2. Variation of crack width 24
2.5. Volume stability 24
2.5.1. Shrinkage 24
2.5.2. Creep 25
2.6. Durability 26
2.6.1. Permeability 26
2.6.2. Sorptivity 26
2.6.3. Freeze-thaw resistance 27
2.6.4. High temperature resistance 28
2.6.5. Sulfate resistance 29
2.6.6. Weathering resistance 29
2.6.7. Alkalinity resistance 29
Chapter 3. Quality Control Testing and Inspection 31
3.1. General 31
3.2. Quality control testing 31
3.2.1. Trial batch 31
3.2.2. Fresh properties 32
3.3. Quality inspection 36
3.3.1. Maturity testing 36
3.3.2. Mechanical testing 36
3.3.3. Visual inspection 38
3.4. Summary 40
Chapter 4. Structural Analysis and Modeling 40
4.1. General 41
4.2. Constitutive models for monotonic loading 41
4.2.1. Tensile stress-strain curves 41
4.2.2. Compressive stress-strain curves 42
4.2.3. Flexural and shear capacity 43
4.3. Constitutive models for cyclic loading 46
4.3.1. Tensile stress-strain curves 46
1. Introduction 7
1.1. Scope 7
1.2. Definition 7
1.3. Terminology 8
1.4. Units 8
Chapter 2. Material Specifications 9
2.1. General 9
2.2. Processing 10
2.2.1. Preparation 10
2.2.2. Placement 12
2.2.3. Curing 12
2.3. Mechanical properties 13
2.3.1. Tensile properties 13
2.3.2. Compressive properties 17
2.3.3. Flexural properties 17
2.3.4. Young’s modulus, Poisson’s ratio, fracture toughness, and flaw size distribution 18
2.3.5. Fatigue resistance 20
2.4. Crack width 21
2.4.1. Average and maximum crack width 23
2.4.2. Variation of crack width 24
2.5. Volume stability 24
2.5.1. Shrinkage 24
2.5.2. Creep 25
2.6. Durability 26
2.6.1. Permeability 26
2.6.2. Sorptivity 26
2.6.3. Freeze-thaw resistance 27
2.6.4. High temperature resistance 28
2.6.5. Sulfate resistance 29
2.6.6. Weathering resistance 29
2.6.7. Alkalinity resistance 29
Chapter 3. Quality Control Testing and Inspection 31
3.1. General 31
3.2. Quality control testing 31
3.2.1. Trial batch 31
3.2.2. Fresh properties 32
3.3. Quality inspection 36
3.3.1. Maturity testing 36
3.3.2. Mechanical testing 36
3.3.3. Visual inspection 38
3.4. Summary 40
Chapter 4. Structural Analysis and Modeling 40
4.1. General 41
4.2. Constitutive models for monotonic loading 41
4.2.1. Tensile stress-strain curves 41
4.2.2. Compressive stress-strain curves 42
4.2.3. Flexural and shear capacity 43
4.3. Constitutive models for cyclic loading 46
4.3.1. Tensile stress-strain curves 46
4.3.2. Compression stress-strain curves 48
Chapter 5. Applications and Benefits 50
5.1. General 50
5.2. Bridges and culverts 50
5.2.1. Bridge decks 50
5.2.2. Bridge girders 51
5.2.3. Retaining walls 51
5.2.4 Culverts 53
5.3. Buildings 53
5.3.1. Beams and columns 53
5.3.2. Walls 54
5.4. Water infrastructure 55
5.4.1. Dams 55
5.4.2. Water channels 56
5.5. Subsurface structures 56
5.5.1. Tunnels 56
5.5.2. Basements 57
5.6. Other potential applications 57
Chapter 6: Guidelines for Material Selection, Processing Methods, and Mix Proportions 59
6.1. General 59
6.2. Selection of raw materials 59
6.2.1. Binders 59
6.2.2. Aggregates 59
6.2.2. Fibers 60
6.2.4. Chemical admixtures 61
6.3. Selection of processing approaches 62
6.4. Selection of mixtures 62
6.4.1. Normal mixtures 62
6.4.2. High-strength mixtures 63
6.4.3. High-early-strength mixtures 64
6.4.4. Light-weight mixtures 65
6.4.5. Photo-catalytic mixtures 66
6.4.6. Self-sensing mixtures 66
6.4.7. Low-carbon mixtures 67
References 68