Preface iii 1. Earthquake and Ground Motion 1 1.1Interior of Earth2 1.2 Causes of Earthquakes 4 1.3 Nature and Occurrence of Earthquakes 8 1.4 Seismic Waves10 1.5 Effects of Earthquakes12 1.6 Consequences of Earthquake Damage 14 1.7 Measurements of Earthquakes15 1.8 Strong Ground Motion 22 1.9 Seismic Zoning 25 1.10 Response of Structure to Earthquake Motion 26 1.11 Seismic Design 28 2. Dynamics of Structures and Seismic Response 31 2.1 Modelling of Structures 33 2.2 Equations of Motion 38 2.3 Systems with Single Degree of Freedom39 2.4 Dynamic Response of Single-Storey Structure 40 2.5 Seismic Response of SDOF Structures 47 2.6 Dynamic Response of Spectrum Representation for Elastic Systems50 2.7 Design Spectra for Inelastic Systems 52 2.8 Systems with Multiple Degrees of Freedom53 2.9 Periods and Modes of Vibration of MDOF Systems 56 2.10 Elastic Response of MDOF Systems 57 2.11 Inelastic Response of MDOF Systems 59 2.12 Restoring Force60 2.13 Damping 61 2.14 Damping Values for Building63 2.15 Uncertainties of Dynamic Analysis64 3.Dynamics of Soils and Seismic Response 82 3.1 Stress Conditions of Soil Element 83 3.2 Dynamic Behaviour of Soil 84 3.4 Dynamic Design Parameters of Soils90 3.5 Soil-Structure Interaction92 3.6 Dynamic Analysis of Soil-Structure Systems93 3.7 Seismic Considerations for Foundations94 3.8 Soil Models96 3.9 Test of Soil Characteristics99 4.Conceptual Design 103 4.1 Functional Planning104 4.2 Continuous Load Path105 4.3 Overall Form 106 4.4 Simplicity and Symmetry 107 4.5 Elongated Shapes109 4.6 Stiffness and Strength109 4.7 Horizontal and Vertical Members113 4.8 Twisting of Buildings114 4.9 Ductility 117 4.10 Flexible Building 118 4.11 Framing Systems120 4.12 Effect of Non-Structures123 4.13 Choice of Construction Materials123 5.Introduction to Earthquake-resistant Design 129 5.1 Seismic Design Requirements131 5.2 Regular and Irregular Configurations134 5.3 Basic Assumptions134 5.4 Design Earthquake Loads135 5.5 Basic Load Combinations 136 5.6 Permissible Stresses737 5.7 Seismic Methods of Analysis138 5.8 Factors in Seismic Analysis143 5.9 Equivalent Lateral Force Method 148 5.10 Dynamic Analysis757 5.11 Response Spectrum Method752 5.12 Time History Method154 5.13 Torsion156 5.14 Soft and Weak Storeys in Construction757 5.15 Overturning Moment158 5.16 Other Structural Requirements159 5.17 Earthquake-resistant Design Methods162 5.18 Response Control 163 6. Masonry Buildings 191 6.1 Categories of Masonry Buildings192 6.2 Behaviour of Unreinforced Masonry Walls193 6.3 Behaviour of Reinforced Masonry Walls795 6.4 Behaviour of Walls-Box Action and Bands196 6.5 Behaviour of Infill Walls199 6.6 Improving Seismic Behaviour of Masonry Buildings 202 6.7 Load Combinations and Permissible Stresses209 6.8 Seismic Design Requirements 210 6.9 Seismic Design of Masonry Buildings 211 6.10 Restoration and Strengthening of Masonry Walls215 7. Timber Buildings 238 7.1 Structural Form239 7.2 Connections240 7.3 Roofs250 7.4 Substructure250 7.5 Site Response253 7.6 Fire Resistance 254 7.7 Decay255 7.8 Timber Shear Panel Construction255 7.9 Stud-wall Construction 257 7.10 Brick-Nogged Timber Frame Construction259 7.11 Permissible Stresses261 7.12 Restoration and Strengthening263 8. Reinforced Concrete Buildings 268 8.1 Damage to RCC Buildings269 8.2 Principles of Earthquake-resistant Design of RCC Members270 8.3 Interaction between Concrete and Steel273 8.4 Concrete Detailing-General Requirements 276 8.5 Flexural Members in Frames 275 8.6 Columns and Frame Members Subjected to Bending and Axial Load286 8.7 Special Confining Reinforcement 289 8.8 Joints of Frames295 8.9 Slabs297 8.10 Staircases298 8.11 Upstands and Parapets 301 8.12 Shear Walls301 8.13 Behaviour of Shear Walls302 8.14 Tall Shear Walls305 8.15 Squat Shear Walls309 8.16 Design of Shear Walls311 8.17 Restoration and Strengthening314 8.18 Precast Concrete Construction317 8.19 Prestressed Concrete Construction320 9. Steel Buildings 339 9.1 Behaviour of Steel342 9.2 Materials and Workmanship343 9.3 Steel Frames345 9.4 Ductile Design of Frame Members353 9.5 Flexural Members356 9.6 Frame Members Subjected to Axial Compression and Bending 358 9.7 Connection Design and Joint Behaviour361 9.8 Steel Panel Zones365 9.9 Bracing Members371 9.10 Load Combinations374 9.11 Retrofitting and Strengthening of Structural Steel Frame3 74 10. Non-structural Elements 386 10.1Failure Mechanisms of Non-Structures387 10.2 Effect of Non-Structural Elements on Structural System388 10.3 Analysis of Non-structural Elements390 10.4 Prevention of Non-structural Damage396 10.5 Isolation of Non-structures399 11. Bhuj Earthquake 2001: A Case Study 407 11.1Earthquake Parameters and Effects408 11.2 Buildings410 Appendices I Some Significant Earthquakes in India420 II Seismic Zones in India 421 Til Zone Factor for Some Important Towns in India422 IV Definitions of Irregular Buildings-Plan Irregularities423 V Definitions of Irregular Buildings-Vertical Irregularities424 VI Horizontal Seismic Coefficient (ao)426 VII Importance Factor (/)426 VIII Soil-foundation Factor (B)426 IX Second-Order Effects (P-A Effects)427 Bibliography 429 Index 443