Compressed Earth Block & Rammed Earth Structures

✍ Scribed by B. V. Venkatarama Reddy

• Publisher: Springer
• Year: 2022
• Tongue: English
• Leaves: 475
• Series: Springer Transactions in Civil and Environmental Engineering
• Category: Library

✦ Synopsis

The book focuses on low carbon construction materials such as stabilised compressed earth blocks (CEB’s) and rammed earth (RE). The content has been divided into four broad themes which includes an introduction to earth construction & stabilised earth, stabilised compressed earth blocks and masonry, stabilised rammed earth, and energy, carbon emissions, sustainability and case studies. It provides basic introduction to earthen materials and earthen structures, particularly with reference to the contemporary work on stabilised earth products for structural applications in buildings. The illustrations in the form of graphs, tables and photographs help the reader to get a grip over the CEB and RE construction. The book illustrates many case studies and examples of CEB and RE buildings. The knowledge on structural characteristics of CEB and RE especially with reference to the durability of such earthen products, and the structural design aspects is uniquely dealt. The embodied energy, embodied carbon, and the impact on construction sector touching upon sustainability of buildings is another unique feature of the book. This volume will be a useful guide for the research community, teachers, engineers, architects, building professionals, practicing engineers, students and individuals aspiring to build low carbon and sustainable buildings.

✦ Table of Contents

Foreword
Preface
Acknowledgements
About This Book
Contents
About the Author
Part I Introduction to Earth Construction and Soil Stabilisation
1 Earthen Materials and Earthen Structures
1.1 History of Earthen Structures
1.2 Earthen Structures in Twentieth–Twenty-First Century
1.2.1 Unstabilised Earthen Structures in Twentieth–Twenty-First Century
1.2.2 Stabilised Earth Structures in Twentieth–Twenty-First Century
1.3 Prefabricated Rammed Earth Construction
1.4 Codes and Norms on Stabilised CEB and Stabilised Rammed Earth
1.5 Energy, Emissions, Environment and Earthen Structures
1.6 Scope and Structure
References
2 Soils
2.1 Soil Formation
2.2 Soil Particle Size
2.3 Clay Minerals
2.3.1 Identification of Clay Minerals
2.4 Some Common Terms, Definitions and Soil Classification
2.5 Particle Size Distribution
2.6 Classification of Soils
2.7 Commonly Occurring Soils
References
3 Soil Stabilisation
3.1 Introduction
3.2 Need for the Stabilised Earth Products in Superstructure
3.3 Soil Stabilisation Techniques
3.3.1 Mechanical Stabilisation
3.3.2 Stabilisation by Compaction
3.3.3 Stabilisation by Additives
3.4 Cement Stabilisation
3.5 Lime Stabilisation
3.5.1 Burning of Limestone
3.5.2 Slacking of Lime
3.5.3 Lime-Clay Reactions
3.6 Soil Compaction
3.6.1 Soil as a Three-Phase System
3.6.2 Soil Compaction Process
3.6.3 Dynamic Compaction
3.6.4 Factors Affecting Soil Compaction
3.6.5 Static Compaction of Soils
3.6.6 Compaction of Soils to Produce Compressed Earth Block (CEB)
3.6.7 The Static Compaction Test
3.6.8 Comparison Between Static Compaction Test and Standard Proctor Test
References
Part II Stabilised Compressed Earth Blocks and Masonry
4 Stabilised Compressed Earth Block Production
4.1 Introduction
4.2 Soil Selection, Excavation and Transportation
4.2.1 Soil Selection
4.2.2 Excavation and Transportation
4.3 Soil Processing for CEB or Rammed Earth Production
4.3.1 Pulverising the Soil
4.3.2 Sieving
4.3.3 Modifying the Soil Composition
4.3.4 Mixing Soils, Aggregates and Binders
4.3.5 Mixing Soil-Binder Mixture and Water
4.4 Stabilised Compressed Earth Block Production
4.4.1 CEB Production Process
4.4.2 Analysis of CEB Production Process
4.5 Curing
4.5.1 Curing by Keeping the Stack of CEBs in Moist Condition
4.5.2 Steam Curing at Atmospheric Pressure
4.6 Machines to Produce Stabilised Compressed Earth Blocks
4.6.1 Manual Machines
4.6.2 Mechanised and Semi-mechanised Machines
References
5 Characteristics of Stabilised Compressed Earth Blocks
5.1 Introduction
5.2 Factors Affecting the Strength Characteristics of Stabilised Compressed Earth Block
5.3 Influence of Soil Composition on the Strength of Stabilised Compressed Earth Block
5.3.1 Soil Reconstitution
5.3.2 Optimum Soil Grading for Stabilised Compressed Earth Bricks/blocks
5.3.3 Chemical Properties of Soils and the Strength Development in Stabilised CEB
5.3.4 Organic Matter and Soil Stabilisation
5.4 Density, Strength and Moulding Moisture Content
5.4.1 Density and Strength Relationships
5.4.2 Density, Moulding Moisture and Strength Relationships
5.5 Strength and Stabiliser Content
5.5.1 Cement Stabilised Compressed Earth Products
5.5.2 Lime Stabilised Compressed Earth Blocks
5.6 Effect of Curing Conditions on the Strength Development in Stabilised CEB
5.6.1 Moist Curing
5.6.2 Steam Curing
5.7 Wet and Dry Compressive Strength of Stabilised Compressed Earth
5.8 Long-Term Strength of Stabilised Compressed Earth Products
5.9 Absorption Characteristics of Stabilised Compressed Earth Products
5.9.1 Water Absorption or Saturated Water Content
5.9.2 Rate of Water Absorption in Cement Stabilised Compressed Earth Bricks/blocks
5.9.3 Initial Rate of Absorption
5.10 Stress–Strain Characteristics of Cement Stabilised Compressed Earth Blocks
5.11 Thermal Characteristics of Stabilised Compressed Earth Blocks
5.12 Durability of Stabilised Compressed Earth Blocks
5.13 Types of Damages in Stabilised Earth Brick/block Masonry Buildings
5.14 Deterioration Mechanisms in Stabilised Earth Products
5.15 Evaluation of Durability Characteristics of Stabilised Earth Products
5.15.1 Spray Erosion Test
5.15.2 Drip Test
5.15.3 Cyclic Wetting and Drying Test
5.15.4 Linear Expansion on Saturation
5.15.5 Usefulness of LES and Mass Loss Values
5.15.6 Freeze–Thaw Test
5.16 Performance of Plastered Stabilised CEB Wall Surfaces
5.17 Summary on Durability of Stabilised CEB
5.18 Retrofitting the Damaged Stabilised Compressed Earth Block Masonry Walls
5.18.1 Patch Plastering with Cement-Soil Mortar
5.18.2 Providing Additional Skirting of Stabilised CEB Veneer on the Damaged Walls
5.18.3 Progressively Replacing the Damaged Stabilised CEB Wall
References
6 Mortars for Stabilised Compressed Earth Block Masonry
6.1 Introduction
6.2 Mortar Constituents
6.3 Fine Aggregate for Mortars
6.4 Types of Mortars
6.5 Mortar Characteristics
6.5.1 Workability of Mortar
6.5.2 Compressive Strength of the Mortar
6.5.3 Water Retentivity
6.5.4 Drying Shrinkage of Mortars
6.5.5 Development of Bond (Adhesion) with the Brick or Block
6.5.6 Stress–Strain Characteristics and Modulus of Mortars
6.6 Selection of Mortar
6.6.1 Masonry Type and the Strength of the Masonry Unit
6.6.2 Masonry Application
6.6.3 Load Carrying Capacity of the Masonry
6.6.4 Moisture Penetration and Frost Resistance
6.7 Mortars for Stabilised Compressed Earth Block Masonry
References
7 Stabilised Compressed Earth Block Masonry
7.1 Introduction
7.2 Bond Strength in Stabilised Compressed Earth Block Masonry
7.2.1 Mechanism of Bond Development
7.2.2 Surface Texture of Cement Stabilised Compressed Earth Blocks
7.2.3 Rate of Water Absorption in Stabilised CEB
7.2.4 Assessing Bond Strength
7.2.5 Optimum Moisture Content in the Stabilised CEB for Bond Development
7.3 Flexure Strength of Stabilised CEB Masonry
7.3.1 Flexure Bond Strength
7.3.2 Flexure Strength of Stabilised CEB Masonry Walls
7.4 Shear Strength of Stabilised Compressed Earth Block Masonry
7.5 Compressive Strength of Stabilised Compressed Earth Block Masonry
7.5.1 Compressive Strength of the Masonry Unit and the Mortar
7.5.2 Masonry Under Compression
7.5.3 Factors Influencing the Compressive Strength of Stabilised CEB Masonry Walls
7.5.4 Compressive Strength of Stabilised CEB Masonry Elements
7.5.5 Influence of Joint Thickness on the Stabilised CEB Masonry Compressive Strength
7.5.6 Compressive Strength of Stabilised CEB Masonry Walls
7.6 Stress–Strain Characteristics of Mortars, Stabilised CEB and CEB Masonry
References
8 Design of Stabilised Compressed Earth Block Masonry
8.1 Design for Gravity Loads
8.2 Design Procedure for Gravity Loading as Per NBC (2016) Code
8.2.1 Stress Reduction Factors
8.3 Design Procedure for Gravity Loading as Per Eurocode-6 (BS EN 1996-1-1:2005+A1:2012)
8.4 Stabilised CEB Masonry Design Using Working Stress Method
8.4.1 Example 1—Design of a Dormitory
8.4.2 Example 2—Six Storey Load Bearing Structure
8.5 Stabilised CEB Masonry Design Using Limit State Method
8.5.1 Example 3—Design of a Dormitory
References
9 Geopolymer or Alkali Activated Stabilised Earth Bricks
9.1 Geopolymers or Alkali Activated Binders
9.2 Reaction Mechanisms in Geopolymerisation or Alkali Activation Processes
9.3 Alkali Activated/geopolymer Binders for Stabilised Compressed Earth Bricks
9.4 Efflorescence in the Geopolymer Stabilised Compressed Earth Products
9.5 Effect of Salt Leaching on the Strength of Geopolymer Stabilised Compressed Earth Specimens
9.6 Characteristics of Geopolymer Stabilised Compressed Earth Bricks
9.6.1 Production of Geopolymer Stabilised CEB
9.6.2 Characteristics of Geopolymer Stabilised Compressed Earth Bricks
References
10 Compressed Earth Blocks Using Non-organic Solid Wastes
10.1 Non-organic Solid Wastes
10.2 Characteristics of Stabilised Compressed Earth Blocks Using NOSW’s
10.2.1 Stabilised Compressed Earth Blocks Using Iron Ore Tailings
10.2.2 Stabilised Compressed Earth Blocks Using C&D Waste
10.2.3 Stabilised Compressed Blocks Using Gold Mine Tailings
10.2.4 Stabilised Compressed Earth Blocks Using Fly Ash
10.2.5 Stabilised Compressed Earth Blocks Using Slag
10.3 Summary
References
Part III Stabilised Rammed Earth
11 Introduction to Rammed Earth
11.1 Rammed Earth
11.2 History and Developments in Rammed Earth Construction
11.3 Method of Casting Rammed Earth
11.3.1 Setting the Mould
11.3.2 Processing the Soil and Preparation of the Mix
11.3.3 Compacting the Processed Material
11.3.4 Dismantling the Formwork and Curing
11.4 Rammed Earth Structures—Potential and Prospects
References
12 Compressive Strength of Rammed Earth
12.1 Compressive Strength
12.2 Optimum Soil Grading
12.3 Optimum Moisture Content
12.3.1 Influence of Soil Grading and Cement Content on the Compaction Characteristics
12.4 Moulding Moisture Content, Density and Strength
12.5 Optimum Layer Thickness
12.6 Effect of Delayed Compaction on the Compaction Characteristics and the Strength of Cement Stabilised Rammed Earth
12.6.1 Compaction Characteristics
12.6.2 Compressive Strength and Time Lag
12.7 Influence of Stabiliser Content on the Compressive Strength of Rammed Earth
12.8 Moisture Absorption in Stabilised Rammed Earth
12.8.1 Influence of Density and Cement Content on Water Absorption
12.9 Moisture Content and Strength of Stabilised Rammed Earth
12.10 Comparison of Strengths of Rammed Earth and Masonry
References
13 Stress–Strain Characteristics of Cement Stabilised Rammed Earth
13.1 Introduction
13.2 Stress–Strain Characteristics of Cement Stabilised Rammed Earth
13.3 Influence of Soil Composition on the Stress–Strain Characteristics
13.4 Cement Content and Modulus Relationships
13.5 Modulus and Density Relationships
13.6 Strength and Modulus Relationships
13.7 Poisson’s Ratio, and Strains at Peak Stress and at Failure
References
14 Behaviour of Rammed Earth Under Tension and Shear
14.1 Introduction
14.2 Flexure Strength of Rammed Earth
14.2.1 Behaviour of Unreinforced Rammed Earth Under Flexure
14.2.2 Behaviour of Reinforced Rammed Earth Under Flexure
14.3 Shear Strength of Rammed Earth
14.3.1 Shear Strength Parameters and Mohr–Coulomb Failure Envelopes
14.3.2 Tri-axial Shear Test
14.3.3 Shear Strength Parameters and Failure Envelopes for CSRE
14.3.4 Triplet Shear Strength
14.3.5 Diagonal Tension (Shear) Strength
References
15 Structural Design of Rammed Earth Walls
15.1 Introduction
15.2 Characteristic Compressive Strength of Rammed Earth
15.3 Slenderness and Strength
15.4 Effect of Load Eccentricity and Slenderness on the Compressive Strength
15.4.1 The Lateral Deflection
15.4.2 Failure Patterns Under Eccentric Loading
15.5 Stress Reduction Factors
15.6 Shrinkage and Construction Joints
15.6.1 The Swell–Shrink Phenomenon in Cement Stabilised Rammed Earth
15.6.2 Movement Construction Joints in Rammed Earth Walls
15.7 Structural Design of Stabilized Rammed Earth Wall
15.7.1 Design for Compression and Bending
15.8 Design Example for CSRE Using Limit State Method
References
Part IV Energy, Carbon Emissions and Sustainability
16 Status of Clay Minerals in the Stabilised Earth Materials
16.1 Introduction
16.2 Soil Composition and Clay Minerals
16.3 Cement and Lime Stabilisation
16.3.1 Cement Stabilisation
16.3.2 Lime Stabilisation
16.4 Assessing Residual Clay Minerals in the Stabilised Compressed Earth Products
16.5 X-Ray Diffraction (XRD) Patterns, SEM Examination and EDS Analysis
16.6 Particle Size Analysis and Clay Size Fraction
16.6.1 Effect of Grinding Duration on Particle Size Fractions
16.6.2 Particle Size Analysis and Clay Size Fractions in Cement and Lime Stabilised Compressed Earth Specimens
16.6.3 Atterberg’s Limits
16.7 Summary
References
17 Energy, Carbon Emissions and Sustainability of Construction Materials and Buildings
17.1 Energy and Carbon Emissions
17.2 Embodied Energy and Carbon Emissions in Stabilised Earth Products
17.3 Embodied Energy and Carbon Emissions in Geopolymer and Lime-Pozzolana Stabilised CEB and Rammed Earth
17.4 Embodied Energy and Carbon Emissions in Buildings
17.5 Sustainability
17.6 Construction Materials
17.7 Sustainability and Greenness
17.8 Material and Energy Resources Consumption
17.8.1 Material Resources
17.9 Rating Systems and the Material Resources Consumption
17.10 Raw Materials Extraction/Management
17.11 Recycling Solid Wastes and By-Products into Building Products
17.12 Sustainability of Green Buildings
17.13 Summary
References
Index