Contents. 1.1 Introduction 1

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1 Contents PREFACE 1 ANCIENT MASONRY Introduction History of Masonry Materials Stone Clay Units Calcium Silicate Units Concrete Masonry Units Mortars Early Building Elements Building Up Spanning Across Enclosing Space Development of Building Structure Posts and Lintels Vaults and Domes Gothic Single-Story Loadbearing Buildings Multistory Loadbearing Buildings Performance of Existing Structures Restoration and Retrofit of Heritage Structures Closure 31 iii

2 1.8 References Problems 32 2 CONTEMPORARY MASONRY Introduction Masonry Elements Walls Columns and Pilasters Beams and Lintels Masonry Building Systems Single-Story Loadbearing Buildings Multistory Loadbearing Buildings Hybrid Buildings Types of Masonry Construction Unreinforced Masonry Reinforced Masonry Prestressed Masonry Research, Codes and Standards Sources of Information Closure References Problems 56 3 BUILDING DESIGN Introduction Structural Elements Design Criteria Structural Design Loads 60 iv

3 3.3 Environmental Requirements Temperature Control Sound Control Moisture Control Fire Control Aesthetics Integration of Requirements Planning the Building Building Form Elevation Plan Wall Configuration and Layout Building Irregularities Floors and Roofs Connections Movement Joints and Joints Between Adjoining Elements Foundations Economic Aspects Closure References Problems MASONRY MATERIALS Introduction Common Properties of Masonry Units Description and Geometry of Masonry Units Properties of Masonry Units Clay Masonry Units Manufacture Grades Sizes and Shapes Compressive Strength Tensile Strength 119 v

4 4.3.6 Absorption Properties Freeze-Thaw Durability Thermal Movement Moisture Expansion Creep Freezing Expansion Selection of Brick Units Concrete Masonry Units Manufacture Grades, Types and Density Sizes and Shapes Compressive Strength Tensile Strength Absorption Durability Thermal Movement Shrinkage Creep Calcium Silicate Units Manufacture Grades and Durability Sizes and Shapes Compressive and Tensile Strengths Absorption Thermal Movement, Shrinkage and Creep Building Stone Groups Sizes, Shapes and Finishes Physical Requirements Durability Thermal Movement Glass Masonry Units Special Nonconventional Masonry Units Interlocking Mortarless Units AAC Masonry Units Mortar Functions of Mortar Mortar Types 140 vi

5 4.9.3 Properties of Plastic Mortar Properties of Hardened Mortar Mortar Aggregates Admixtures and Colors Grout Workability Requirements Types Admixtures Compressive Strength Reinforcement Reinforcing Bars Joint Reinforcement Connectors Prestressing Steels Corrosion Protection Associated Materials Movement Joint Filler Materials Dampproofing Parging Flashing and Weep Holes Air Barriers and Vapor Barriers Coatings Insulation Closure References Problems MASONRY ASSEMBLAGES Introduction Axial Compression Introduction Standard Prism Tests General Failure Mechanism Factors Affecting Prism Strength Stress-Strain Relationships 179 vii

6 5.2.6 Relationship Between Wall Strength and Prism Strength Compressive Strength for Loading Parallel to Bed Joint Combined Axial Compression and Flexure Introduction Prism Tests General Failure Mechanisms Factors Affecting the Influence of Strain Gradient Compression Stress-Strain Relationship Flexural Tensile Strength for Out-of-Plane Bending Introduction Test Methods Failure Mechanisms Factors Affecting the Tensile Bond Between Masonry Units and Mortar Factors Affecting the Flexural Tensile Strength of Grout-Filled Hollow Masonry Orthogonal Strength Ratio Biaxial Strength Shear Strength Along Mortar Bed Joints Introduction Test Methods Failure Modes Relationships Between Shear Strength Along Bed Joints and Normal Compressive Stress Interaction of Shear and Tension Along Bed Joints Factors Affecting the Shear Strength Along Mortar Bed Joints Shear Strengths of Collar Joints and Head Joints In-Plane Tensile Strength Introduction Test Methods Failure Modes Factors Affecting In-Plane Tensile Strength Combined Loading and Biaxial Strength Introduction Test Methods Failure Modes Factors Affecting Failure Loads Under Biaxial Compression-Tension Stresses 215 viii

7 5.8 Examples Example 5.1: Bearing Plate for Prism Test Example 5.2: Selection of Masonry Unit and Mortar Example 5.3: Axial Deformation Under Load Example 5.4: Effect of Grouting in Increasing Joint Shear Strength of Concrete Masonry under In-Plane Loads Example 5.5: Modulus of Rupture of Partially Grouted Concrete Masonry Example 5.6: Effect of Grouting on Increasing Moment Carrying Capacity of Concrete Masonry Under Out-of-Plane Loads Example 5.7: Orthogonal Tensile Strength Ratio of Brick Masonry Example 5.8: Orthogonal Tensile Strength Ratio of Brick Masonry Closure References Problems REINFORCED BEAMS AND LINTELS Introduction Flexural Behavior and Design Fundamental Assumptions Behavior of Beams with Tension Reinforcement Elastic Analysis of Beams with Tension Reinforcement Strength Analysis of Beams with Tension Reinforcement Design Considerations Example 6.1: Beam Flexural Analysis Example 6.2: Flexural Design Shear Behavior and Design Shear Cracking (Diagonal Tension Cracking) Behavior Development of Design Methods Example 6.3: Shear Design Development, Anchorage and Splicing of Reinforcement General Requirements Development Length for Reinforcement Example 6.4: Bond and Development Length 255 ix

8 6.5 Serviceability Requirements General Deflection Example 6.5: Deflection Calculation Load Distribution on Lintel Beams Behavior Example 6.6: Lintel Beam Loading Example Software for Lintel Design Closure References Problems FLEXURAL WALL Introduction Load-Resisting Mechanisms Flexural Behavior of Unreinforced Walls Background Vertical Flexure (Single-Wythe) Effect of Superimposed Axial Load Horizontal Flexure (Single-Wythe) Two-Way Flexure (Single-Wythe) Multiple-Wythe Walls Analysis and Design of Unreinforced Walls Introduction Design from Basic Principles Yield Line and Failure Line Design Methods Application of Failure Line Design for Flexural Wall Panels Example 7.1: Two-Way Bending Diaphragm Walls Glass Block Panels Masonry Partition Walls Arching Mechanics of Rigid Arching 286 x

9 7.5.2 Mechanism of Gapped Arching Influence of Axial Shortening on Arching Mechanism Influence of Movement of Supports on Arching Mechanisms Design Example 7.2: Arching Action of URM Wall Reinforced Flexural Walls Background Vertical One-Way Flexural Behavior Horizontal One-Way Flexural Behavior Two-Way Flexural Behavior Analysis and Design of Reinforced Flexural Walls Vertical Flexural Design Horizontal Flexural Design Two-Way Flexural Design Walls with Openings Reinforced Cavity and Veneer Walls Limits on Spacing and Amount of Reinforcement Partially (Nominally) Reinforced Walls Shear Design Anchorage of Reinforcement Reinforced Flexural Wall Design Examples Example 7.3: Vertically Spanning Reinforced Concrete Block Wall Example 7.4: Two-Way Bending of Reinforced Concrete Block Wall Prestressed Masonry Walls Introduction Behavior of Prestressed Walls under Lateral Loads Design Methods Permissible Stress in Prestressing Tendons Strength Requirements Slenderness Effects Shear Design Deflection under Service Loads Example 7.7: Design of Nonloadbearing Walls to Resist Wind Pressure Closure References 317 xi

10 7.12 Problems LOADBEARING WALLS UNDER AXIAL LOAD AND OUT-OF-PLANE BENDING Introduction Overview of Status and Trends in Design Provisions Current Status of Design Provisions Types of Wall Construction Analysis and Design under Combined Axial Load and Bending Stress-Strain Relationships for Masonry and Steel Design of Unreinforced Masonry Section Analysis of Solid Unreinforced Masonry Section Analysis of Reinforced Masonry Effects of Slenderness Introduction TMS 402 Code Provisions for Slenderness Discussion Concentrated Loads Introduction State of Stress Under Concentrated Loads Strength Enhancement Factor Design Provisions Limiting Compressive Stress for Bearing Design Examples Example 8.1: Strength Analysis of Unreinforced Wall Under Concentric Axial Compression Example 8.2: Design of Concrete Block Wall Under Eccentric Axial and Wind Loads Example 8.3: Analysis of Bearing Capacity Under Concentrated Load Closure References Problems 348 xii

11 9 COLUMNS AND PILASTERS Introduction Column Behavior Introduction Failure Modes and Compressive Strength Slenderness Effect Column Design Design Considerations Design of Columns Under Axial Load and Uniaxial Bending Design of Columns under Biaxial Bending Seismic Design Considerations Column Design Examples Example 9.1: Design of Column Under Concentric Axial Compression Example 9.2: Eccentrically Loaded Column Example 9.3: Design of a Column Under Biaxial Bending Pilaster Design Introduction Load Sharing Between Walls and Pilasters Example 9.4: Pilaster Design Using TMS 402 Strength Design Method Closure References Problems SHEAR WALLS Introduction Influence of Types and Layout of Shear Walls Behavior and Failure Modes Unreinforced Shear Walls Multistory Unreinforced Shear Walls 377 xiii

12 Fully Grouted Reinforced Masonry Shear Walls Fully Grouted Reinforced Masonry Shear Walls With Openings Multistory Fully Grouted Reinforced Masonry Shear Walls Partially Grouted Reinforced Masonry Shear Walls Partially Grouted Reinforced Masonry One-Story Buildings Distribution of Loads to Shear Walls Gravity Loads Lateral Forces Factors Affecting the Distribution of Lateral Loads Effect of Openings on Wall Rigidity and Force Distribution Horizontal and Vertical Combinations of Shear Wall Segments Rigidity of Walls with Openings in Low-Rise Buildings Example 10.1: Lateral Load Distribution to Walls in a Low-Rise Building Multistory Shear Walls Example 10.2: Forces on Piers in Multistory Walls with Openings Limit Analysis of Reinforced Masonry Shear Walls Design of Shear Walls Unreinforced Shear Walls Reinforced Shear Walls Special Seismic Design Considerations Moment-Resisting Wall Frames Limit Design of Special Reinforced Masonry Shear Walls Wall Connections Design Examples Example 10.3: Unreinforced Shear Wall Example 10.4: Reinforced Shear Wall Example 10.5: Pier in a Perforated Wall Example 10.6: Seismic Design of a Perforated Two-Story Reinforced Masonry Shear Wall Example 10.7: Example of Ductility Calculations of a Multistory Shear Wall Example 10.8:Shear Strength of Partially Grouted Shear Walls Closure References Problems 443 xiv

13 11 INFILL WALLS AND PARTITIONS Introduction Infill Walls Behavior of Participating Infill Not Anchored to Frames for Composite Action Analysis of Infilled Frames Strength of Infill Walls Infill Walls With Openings Infill Walls With Movement Joints at the Top Transverse Strength of Participating Infill Walls Seismic Design Considerations Example 11.1: Elastic Analysis of the Initial Elastic Stiffness of an Infilled Frame Example 11.2: Cracked Stiffness of An Infilled Frame Example 11.3: Design of Infill Wall Walls Supported on Beams Introduction Interaction Mechanism and Failure Modes Analysis Limitations of Analysis Example 11.4: Masonry Wall Supported on a Beam Closure References Problems MASONRY VENEER AND CAVITY WALLS Introduction Background Components of Masonry Veneer and Cavity Walls Critical Features in Design and Construction Masonry Rain Screen Walls Introduction Design of Masonry Veneer Rain Screens Additional Precautions to Avoid Rain Penetration 492 xv

14 Detailing Requirements for Rain Screen Performance Shelf Angle Supports Design of Anchors for Shelf Angles Example 12.1: Calculation of Anchor Connection Design of Shelf Angles Flashing Materials Construction Details for Shelf Angles Structural Design Considerations Structural Requirements for Masonry Veneer Walls Structural Requirements for Masonry Cavity Walls Requirements for Ties and Anchors Special Design Considerations for High Seismic Intensity Areas Design for Movement Joints Horizontal Movement Joints Vertical Movement Joints Residential Construction of Brick Veneer Adhered Veneer Closure References Problems CONNECTORS Introduction Wall Ties Basic Functions Performance Requirements Types of Ties Strength Stiffness Adjustability Design Considerations for Cavity Wall Ties Analysis of Load Distribution Example 13.1: Tie Forces in Cavity Walls 529 xvi

15 Construction Considerations Tie Materials and Corrosion Resistance Anchors Veneer Anchors Non-Veneer Anchors Design and Construction Considerations Fasteners Basic Functions Types of Fasteners Strength of Anchor Bolts Design of Fasteners Example 13.2: Anchor Bolt Design Closure References Problems FIRE RESISTANCE AND DESIGN FOR ENVIRONMENTAL LOADS Introduction Applications of Building Science to Masonry Construction Fire Resistance Introduction Design Practice Fire-Resistance Rating Methods for Increasing Fire Resistance Other Aspects of Fire Protection Example 14.1: Design for Fire Resistance of a Nonloadbearing Partition Example 14.2: Calculation of Fire Resistance of a Multi-wythe Wall Thermal Performance Introduction Introduction to Heat Transfer at Building Surfaces Heat Transfer and Thermal Resistance 561 xvii

16 Example 14.3: Thermal Resistance and Temperatures in a Cavity Wall Other Factors Affecting Thermal Resistance of Masonry Walls Thermal Inertia Other Considerations Condensation Considerations Introduction Water Vapor Condensation Example 14.3 (continued): Potential for Water Vapor Flow Diffusion of Water Vapor and Potential for Condensation Condensation from Airborne Moisture Example 14.3 (continued): Calculation of Condensation Due to Exfiltration of Air Interaction Between Air and Vapor Barriers Rain Penetration Background Factors Affecting Rain Penetration Design Provisions to Minimize the Potential for Rain Penetration Measurement of Water Permeance Sound Control Introduction Sound Transmission Sound Transmission Loss Sound Absorption Noise Barrier Walls Other Design and Construction Considerations Closure References Problems CONSTRUCTION CONSIDERATIONS AND DETAILS Introduction Workmanship and Construction Practices Effect of Workmanship on Strength 597 xviii

17 Effect of Workmanship on Water Permeance Preparations in Advance of Laying Masonry Preparation of Mortar Mixes Use of Mortar Laying of Units Reinforcing and Grouting Tolerances Influence of Weather on Construction Requirements Cold Weather Construction Hot Weather Construction Wet Weather Construction Construction in Windy Weather Protection of Masonry During Construction Covering and Curing Avoiding Unintended Loads Wind Bracing Flashing and Dampproof Courses Description Installation of Flashings and Dampproof Courses Effect on Wall Strength Movement Joints Functions and Types of Movement Joints Spacing, Location and Size Requirements Joint Sealants Construction Details Connection Details More Competitive Masonry Construction Robotics in Masonry Construction Increasing Productivity of Masons Dry-Stack Interlocking Mortarless Masonry Inspection and Quality Control Introduction Quality Assurance and Quality Control Inspection Closure 637 xix

18 15.11 References Problems DESIGN OF LOADBEARING SINGLE-STORY MASONRY BUILDINGS General Introduction Behavior, Form and Layout Wall Layout Requirements for Stability Wall Layout to Resist Lateral Loads Example 16.1: Lateral Load Distribution for a Rigid Diaphragm Roof System Example 16.2: Lateral Load Distribution for a Nonrigid Roof System Effect of Shear Wall Deflection on Out-of-Plane Wall Behavior Example 16.3: Effect of Top Deflection on Out-of-Plane Bending in Walls Design Loads Gravity Loads Wind Loading Seismic Loading Design of Components Design of Walls for Axial Load and Bending Design of Walls for In-Plane Shear and Bending Design Requirements for Roof Diaphragms Example 16.4: Extra Stiffening of the Roof Design of Walls for Hold-Down of Roof Systems Example 16.5: Hold-Down of a Roof Example Design of Single-Story Building Introduction Description of the Building Design Loads Design of a Typical Wall for Axial Load and Out-of-Plane Bending Design of Other Walls and Walls with Openings for Axial Load and Out of-plane Bending Design of Walls for Uplift Forces Design of Walls for In-Plane Shear and Bending Required Stiffness of Roof Diaphragm 674 xx

19 Bearing Other Considerations Closure References Problems DESIGN OF MULTI-STORY LOADBEARING MASONRY BUILDINGS Introduction Basic Design Concepts Introduction Vertical Load Transfer Lateral Load Transfer Distribution of Shear and Moment Due to Lateral Load Relative Wall Rigidity for Structural Analysis Choice of Method for Determination of Relative Wall Rigidity Other Factors Affecting the Distribution of Lateral Loads Torsional Effects Basic Concept Calculation of Torsional Moments Design Example of Multistory Building Description of the Building Loads Calculation of Lateral Forces Distribution of Lateral Loads to Shear Walls Calculation of Shear Forces and Moments at the Base of the Shear Walls Material Properties Drift Calculations Wall Design Out-of-Plane Loading In-Plane Loading (Shear Walls) Closure References 721 xxi

20 17.8 Problems 722 Appendix A : Sources of Information 725 Appendix B: Design Information Material Properties 731 Index 737 xxii