Testing and Characterisation of Earth-based Building Materials and Elements: State-of-the-Art Report of the RILEM TC 274-TCE

Description

This book presents the work done by the RILEM Technical Committee 274-TCE. It focuses on the estimation of the parameters which are necessary to properly design earthen constructions. It provides a compilation of the value classically obtained for the key parameters of earthen materials, a pedagogical presentation of the main testing procedures for earthen materials, their advantage and their drawback and an overview of most standards on earthen materials, whatever their origin and their language.The book is divided into eight chapters. After a general introduction on earthen materials and constructions, the state of the art on the material characterisation technics, the assessment of hygrothermal performance, the mechanical behaviour, seismic resistance and the durability will be presented, each in a dedicated chapter. On the basis of these last chapters, a critical review of the standards which are used for earthen material will be presented in the last chapter. The last chapter is dedicated to the analysis of the environmental potential of earth-based building materials. RILEM Technical Committee 274-TCE RILEM Publications Contents Contributors 1 General Introduction 1.1 The Origin of Earth 1.2 Historical Overview 1.3 Classification and Definition of Earth Building Processes 1.4 Why Building with Earth? 1.4.1 Saving Natural Resources 1.4.2 Energy 1.4.3 Indoor Comfort 1.4.4 Social Impact 1.5 The Challenge for Modern Earth Building 1.6 Conclusion References 2 Characterization of Earth Used in Earth Construction Materials 2.1 Introduction 2.2 Global Analysis of References Used for This Review—Methodology 2.3 Particle Size Distribution 2.3.1 Procedures and Standards 2.4 Physical and Geotechnical Characterization 2.4.1 Procedures and Standards 2.4.2 Study of Data from Literature 2.5 Chemical Characterisation 2.5.1 Procedures and Standards 2.5.2 Study of Data from Literature 2.6 Mineralogical Characterisation 2.6.1 Procedures and Standards 2.6.2 Study of Data from Literature 2.7 Field Tests 2.7.1 Procedures and Standards 2.7.2 Study of Data from Literature 2.8 Conclusion Appendix 1: Particle Size Distribution of Earth Construction Materials Appendix 2: Atterberg Limits of Earth Construction Materials Appendix 3: Optimum Proctor Characteristics of Earth Construction Materials References 3 Hygrothermal and Acoustic Assessment of Earthen Materials 3.1 Introduction 3.2 Key Material Parameters Involved in Hygrothermal Couplings 3.2.1 General Diagram of Heat and Mass Transfers 3.2.2 Mass Conservation of Water 3.2.3 Mass Conservation of Air 3.2.4 Heat Balance 3.2.5 Boundary Conditions and Interfaces 3.2.6 Summary on the Key Parameters used for Hygrothermal Simulations 3.3 Laboratory Measurement of Hygrothermal Parameters 3.3.1 Measurement of Thermal Properties 3.3.2 Transport Properties 3.3.3 Water Vapour Sorption Curves 3.3.4 Assessment of the Hygroscopic Buffering and Hygrothermal Potential 3.4 Assessment of In-Situ Thermal and Hygrothermal Performance 3.4.1 Description of the Instrumented Houses 3.4.2 Instrumentation Protocol 3.4.3 Results Obtained on Earthen Buildings 3.5 Acoustic Properties 3.5.1 Measurement of Material Acoustical Properties 3.5.2 Measurement of Building Elements Acoustic Properties 3.6 Conclusion 3.6.1 Concluding Remarks 3.7 Appendix 3.1: Characteristics of Houses and Experimental Cells Built with Other Materials Than Earth References 4 Mechanical Behaviour of Earth Building Materials 4.1 Rammed Earth 4.1.1 Introduction 4.1.2 Mechanical Properties 4.1.3 Full Scale Behaviour and Shear Properties 4.1.4 Experimental Procedure 4.2 Earth Blocks 4.2.1 Introduction 4.2.2 Mechanical Properties 4.2.3 Experimental Procedures 4.3 Cob 4.3.1 Introduction 4.3.2 Mechanical Behaviour 4.3.3 Experimental Procedures References 5 Seismic Assessment of Earthen Structures 5.1 Introduction 5.2 Earth Materials—A Synthesis of Mechanical Characteristics 5.2.1 Compressive Strength 5.2.2 Tensile Strength 5.2.3 Shear Strength 5.2.4 Young’s Modulus 5.2.5 Shear Modulus 5.2.6 Poisson’s Ratio 5.2.7 Density 5.2.8 Friction Angle 5.2.9 Influences of Moisture Content 5.3 Dynamic Characteristics of Earthen Structures 5.3.1 Typical Geometries of Earthen Buildings 5.3.2 Natural Frequencies and Mode Shapes 5.3.3 Damping 5.4 Analytical and Numerical Modelling 5.4.1 Simplified Modelling 5.4.2 Finite Element Modelling 5.4.3 Discrete Element Modelling 5.5 Seismic Assessment 5.5.1 Linear Static Analysis 5.5.2 Non-linear Static Analysis 5.5.3 Response-Spectrum Modal Analysis 5.5.4 Non-linear Dynamic Analysis 5.5.5 Experimental Tests with Shaking Table 5.6 Seismic Strengthening 5.6.1 Adobes Structures 5.6.2 Rammed Earth Structures 5.6.3 Timber Frame Structure with Infill and Timber Laced Masonry 5.7 Conclusions References 6 Durability of Earth Materials: Weathering Agents, Testing Procedures and Stabilisation Methods 6.1 Introduction 6.2 Weathering Actions 6.2.1 Water 6.2.2 Ice 6.2.3 Wind 6.2.4 Fire 6.2.5 Solar Radiation 6.2.6 Chemical Agents 6.3 Field Measurement of Durability 6.4 Laboratory Measurement of Durability 6.4.1 Water 6.4.2 Ice 6.4.3 Wind 6.4.4 Solar Radiation 6.4.5 Fire and Chemical Agents 6.4.6 Standardization of Durability Tests 6.5 Stabilisation Methods for Enhancing Earth Durability 6.5.1 Organic Stabilisation 6.5.2 Inorganic Stabilisation 6.6 Conclusions References 7 Codes and Standards on Earth Construction 7.1 Introduction 7.2 Earthen Structures and Construction Techniques 7.3 Developments in Earth Construction Standardisation 7.4 Types of Earth Building Standards/Codes and Documents 7.4.1 Soil or Earth Composition 7.4.2 Moulds/machinery and Manufacturing Earthen Building Products 7.4.3 Testing/evaluation and Quality Control 7.4.4 Design Guidance 7.4.5 Construction Methodology and Construction Procedure 7.4.6 Earthquake Resistant Guidelines 7.4.7 Durability, Limitations and Maintenance 7.5 Conclusion and Guidelines for Comprehensive Code References 8 Environmental Potential of Earth-Based Building Materials: Key Facts and Issues from a Life Cycle Assessment Perspective 8.1 Introduction 8.2 Method 8.3 Extraction and Production 8.3.1 Influence of Clay Content in Raw Earth 8.3.2 Influence of Binder in Mix Design 8.3.3 Influence of the Scale of Data Collection 8.3.4 Influence of Transports 8.3.5 Influence of the building’s Design 8.4 Use Phase 8.4.1 Maintenance of Earthen Walls 8.4.2 Heating and Cooling Energy: Thermal Aspects 8.5 End of Life 8.6 Comparisons of Earthen Walls to Other Construction Techniques 8.6.1 Comparisons at Wall Scale 8.6.2 Comparisons at Building Scale 8.7 General Discussion 8.8 Conclusion Appendix 1 Calculations of CED and GWP Appendix 2 Available Results Concerning Transport Appendix 3 Available Results Concerning the Maintenance Phase References