Modern Earthquake Engineering (eBook)

Dr. Junbo Jia is an engineering expert at Aker Solutions, Norway. He is currently a committee member of ISO TC67/SC7 Fixed Steel Structures and an invited member of Eurocode 3. He has been invited as speakers, lecturers for industry training and university graduate courses, and permanent members of PhD examination committees by various organizations and research institutes. Dr. Junbo Jia is authors of two other Springer engineering monographs on Applied Dynamic Analysis, and Foundation Dynamics and Modeling. He is currently an editor of a handbook volume: Structural Engineering in Vibrations, Dynamics and Impacts to be published by CRC press in 2018.

Preface 6
About this Book 11
Contents 12
1 Introduction 23
1.1 Historical Earthquake Events 23
1.2 Consequences of Earthquakes 27
1.3 Benefits of Earthquakes 40
1.4 Causes of Earthquakes 41
1.4.1 Tectonic-Related Earthquakes and the Elastic Rebound Theory 42
1.4.2 Volcanic Earthquakes 47
1.4.3 Human Induced/Triggered Earthquakes 49
1.4.4 Ice Induced Earthquakes 55
1.5 Faults 56
1.6 Tectonic Plate Boundaries and Fault Zones 62
1.6.1 Spreading Zones 63
1.6.2 Subduction Zones 66
1.6.2.1 Introduction to Subduction Zones 66
1.6.2.2 Convergent Boundary 66
1.6.3 Transform Fault Zones 70
1.6.4 Intraplates 71
1.6.5 Relation of Plate Boundaries with Earthquake Occurrences 73
1.7 Earthquake Mitigation Measures and Modern Earthquake Engineering 74
1.8 Earthquake Prediction and Forecast 78
1.8.1 Earthquake Prediction 78
1.8.2 Earthquake Forecast 81
1.8.3 The Social and Economic Impact of Earthquake Predictions 81
1.9 Motivations of Offshore Earthquake Engineering 83
1.10 Closing Remarks 90
References 90
2 Offshore Structures Versus Land-Based Structures 95
2.1 Introduction to Offshore Structures 95
2.1.1 Offshore Platforms 95
2.1.2 Offshore Wind Turbine Substructures and Foundations 103
2.2 Accounting of Dynamics in the Concept Design of Structures 109
2.2.1 Dynamics Versus Statics 109
2.2.2 Characteristics of Dynamic Responses 114
2.2.3 Frequency Range of Dynamic Loading 119
2.3 Difference Between Offshore and Land-Based Structures 124
References 128
3 Characterize Ground Motions 129
3.1 Definition of Earthquake Locations 129
3.2 Seismic Waves 129
3.2.1 Body Waves 130
3.2.1.1 P-Wave 130
3.2.1.2 S-Wave 132
3.2.2 Surface Waves 135
3.2.2.1 Love Wave (LQ or G) 136
3.2.2.2 Rayleigh Wave (LR or R) 136
3.2.3 Guided Waves 139
3.3 Measuring Seismic Motions Using Seismogram 141
3.3.1 Measurement Using Seismograph 141
3.3.2 Torsional Seismic Motions 146
3.4 Magnitude and Intensity 146
3.4.1 Magnitude 147
3.4.1.1 Richter (Local) Magnitude 147
3.4.1.2 Surface Wave Magnitude 149
3.4.1.3 Body Wave Magnitude 151
3.4.1.4 Moment Magnitude 152
3.4.1.5 Saturation of Magnitude Measures 154
3.4.2 Intensity Categories 156
3.5 Non-stationary and Peak Ground Motions 159
3.5.1 Peak Ground Motions and Its Relationship with Magnitude and Intensity 159
3.5.2 Contribution of Body and Surface Wave to Ground Motions 162
3.5.3 Moving Resonance 163
3.6 Attenuation Relationship and Uncertainties 164
3.7 Duration of Ground Motions 174
3.7.1 Effects of Ground Motion Durations 174
3.7.2 Definition of Ground Motion Duration 176
3.7.2.1 Bracketed Duration 176
3.7.2.2 Significant Duration 177
3.7.2.3 Uniform Duration 178
3.7.3 Approximation of Ground Motion Duration 179
3.7.3.1 Factors Affecting the Ground Motion Duration 179
3.7.3.2 Estimation of Ground Motion Duration 181
3.8 Source of Ground Motion Recording Data 184
References 184
4 Determination of Site Specific Earthquake Ground Motions 191
4.1 From Fault Rupture to Seismic Design 191
4.2 Site Period 197
4.2.1 General 197
4.2.2 Influence of Soil Depth on the Site Period 201
4.3 Site Response and Soil–Structure Interactions 204
4.3.1 General 204
4.3.1.1 Direct Analysis Approach 205
4.3.1.2 Substructure Approach 205
4.3.2 Kinematic Interaction 207
4.3.3 Subgrade Impedances and Damping 208
4.3.4 Inertial Interaction 208
4.3.5 Effects of Soil–Structure Interaction 209
4.3.6 Characteristics of Site Responses 210
4.3.6.1 Horizontal Ground Motions 210
4.3.6.2 Vertical Ground Motions 211
4.3.7 Effects of Topographic and Subsurface Irregularities 212
4.3.7.1 General 212
4.3.7.2 Effects of Irregular Surface Topology 212
4.3.7.3 Effects of Subsurface Irregularity 214
4.3.8 Applicability of One-, Two-, and Three-Dimensional Site Response Analysis 216
4.3.9 Linear, Equivalent Linear or Non-linear Soil Modeling 217
4.3.10 Location to Input Seimsic Motions for a Site Response Analysis 219
4.4 Water Column Effects on Vertical Ground Excitations 219
References 220
5 Representation of Earthquake Ground Motions 224
5.1 General 224
5.2 Earthquake Excitations Versus Dynamic Ocean Wave, Wind, and Ice Loading 225
5.3 Power Spectrum of Seismic Ground Motions 228
5.3.1 Introduction to Fourier and Power Spectrum 228
5.3.1.1 Fourier Spectrum 228
5.3.1.2 Power Spectrum Density 232
5.3.2 Power Spectrum of Seismic Ground Motions 236
5.4 Response Spectrum 239
5.4.1 Background 239
5.4.2 Elastic Response and Design Spectrum 241
5.4.2.1 Elastic Response Spectrum 241
5.4.2.2 Elastic Design Spectrum 250
5.4.2.3 Effects of Damping 257
5.4.2.4 Shear Wave Velocity Estimation with Shallow Soil Depth or Soils and Rock Below 30 m 259
5.4.3 Ductility-Modified (Inelastic) Design Spectrum Method 260
5.4.3.1 Ductility for Elastic-Perfect-Plastic Structures 260
5.4.3.2 Construction Ductility-Modified (Inelastic) Design Spectrum Method 264
5.4.4 Vertical Response Spectrum 266
5.5 Time History Method 270
5.5.1 General Method 270
5.5.2 Drift Phenomenon and Its Correction 271
5.6 Wavelet Transform Method 275
References 282
6 Determining Response Spectra by Design Codes 288
6.1 General 288
6.2 Code Based Simplified Method for Calculating the Response Spectrum 289
6.2.1 Construction of Design Spectrum in Eurocode 8 for Land-Based Structure 290
6.2.2 Construction of Design Spectrum in ISO 19901 and Norsok for Offshore Structures 293
6.2.2.1 Design Spectrum by ISO 19901 294
6.2.2.2 Design Spectrum by Norsok N-003 298
References 301
7 Record Selection for Performing Site Specific Response Analysis 302
7.1 General 302
7.2 Selections of Motion Recordings 303
7.3 Modification of the Recordings to Fit into the Design Rock Spectrum 304
7.3.1 Direct Scaling 304
7.3.2 Spectrum/Spectral Matching 304
7.3.3 Pros and Cons of Direct Scaling and Spectrum Matching 308
7.4 Performing the Site Response Analysis Using Modified/Matched Recordings 309
References 311
8 Spatial Varied (Asynchronous) Ground Motion 313
8.1 General 313
8.2 Cross-Covariance, Cross-Spectra Density Function and Coherence Function 317
8.2.1 Cross-Covariance in Time Domain 317
8.2.2 Cross-Spectra Density in the Frequency Domain 318
8.2.3 Coherence Function in the Frequency Domain 318
8.3 Simulation of SVEGM 320
8.4 Effects of SVEGM 324
References 328
9 Seismic Hazard and Risk Assessment 331
9.1 Seismic Hazard Analysis 331
9.1.1 Introduction 331
9.1.2 Deterministic Seismic Hazard Analysis (DSHA) 333
9.1.3 Probabilistic Seismic Hazard Analysis (PSHA) 335
9.1.3.1 Define Earthquake Source and Geometry 336
9.1.3.2 Establish Attenuation Relationship 341
9.1.3.3 Develop Seismic Hazard Curve 342
9.1.3.4 Construction of Spectra Acceleration at Discreted Periods 349
9.1.4 Deaggregation (Disaggregation) in PSHA for Multiple Sources 352
9.1.5 Logic Tree Method 356
9.2 Seismic Hazard Map 358
9.3 Apply PSHA for Engineering Design 362
9.4 Conditional Mean Spectrum 366
9.5 Forecasting “Unpredictable” Extremes—Dragon-Kings 371
9.6 Assessing Earthquake Disaster Assisted by Satellite Remote Sensing 373
9.7 Seismic Risk 374
References 376
10 Influence of Hydrodynamic Forces and Ice During Earthquakes 380
10.1 Hydrodynamic Forces 380
10.1.1 Introduction to Hydrodynamic Force Calculation 380
10.1.2 Effects of Drag Forces 385
10.1.3 Effects and Determination of Added Mass 386
10.1.4 Effects of Buoyancy 388
10.1.5 Effects and Modeling of Marine Growth 388
10.2 Effects of Ice 391
10.2.1 General 391
10.2.2 Effects of Ice–Structure Interaction on the Seismic Response of Structures 394
10.2.3 Icing and Its Effects 395
References 396
11 Shock Wave Due to Seaquakes 398
11.1 Introduction 398
11.2 Simplified Model for Simulating Seaquakes 399
11.3 Case Study by Kiyokawa 400
References 404
12 Introduction to Tsunamis 406
12.1 Cause of Tsunamis 406
12.2 History and Consequences of Tsunamis 410
12.3 Characterizing Tsunami Size 412
12.4 Calculation of Tsunami Waves 414
12.4.1 Tsunami Generation at Source 415
12.4.2 Tsunami Propagation in Ocean 418
12.4.3 Tsunami Run-up (Shoaling) at Coastal Areas and Sloped Beach 419
12.4.4 Shallow Water Wave Theory 421
12.5 Tsunami Induced Load on Structures Located in Shallow Water and Coastal Areas 423
12.6 Structural Resistance Due to Tsunami 426
12.7 Mitigation of Tsunami Hazard 427
References 430
13 Earthquake Damages 432
13.1 General 432
13.2 Structural and Foundation Damage 432
13.3 Soil Liquefaction 435
13.3.1 General 435
13.3.2 Assessment of Liquefaction 438
13.3.3 Mitigation Measures of Soil Liquefaction 440
13.4 Landslides 440
13.4.1 General 440
13.4.2 Assessment of Regional Landslide Potential by Arias Intensity 442
13.5 Human Body Safety and Motion Induced Interruptions 443
13.5.1 General 443
13.5.2 Remedial Measures with Regard to Human Body Safety 444
13.5.3 Motion Induced Interruptions 445
13.5.3.1 Sliding/Slipping 445
13.5.3.2 Tipping 446
13.6 Structural Damage Measures 446
13.6.1 Basic Parameters for Damage Measures 446
13.6.2 Damage Indices 447
References 448
14 Design Philosophy 451
14.1 General 451
14.2 Prescriptive Code Design 454
14.2.1 Introduction 454
14.2.2 Limit States Design 455
14.2.3 Allowable Stress Design 457
14.2.4 Plastic Design 459
14.2.5 Load and Resistance Factor Design 460
14.2.5.1 Probability of Failure 460
14.2.5.2 Probability of Failure for Non-linear Safety Margin Functions 471
14.2.5.3 Monte-Carlo Method for Calculating Probability of Failure 474
14.2.6 Levels of Reliability Method 475
14.2.7 ASD Versus LRFD 476
14.2.8 Development of Seismic Design Codes 477
14.2.9 Hierarchy of Codes and Standards 478
14.3 Introduction to Performance-Based Design 480
14.3.1 Limitations of Traditional Prescriptive Code Design 480
14.3.2 Introduction to Performance-Based Design 481
14.3.3 Performance-Based Design for Structures 484
14.3.4 Introduction to Practical Methods for PBD 485
References 486
15 Seismic Analysis and Response of Structures 489
15.1 General 489
15.2 Traditional Seismic Analysis Methods 490
15.2.1 Introduction 490
15.2.2 Simplified Static Seismic Coefficient Method 494
15.2.2.1 Method Description 494
15.2.2.2 Limitations of the Static Coefficient Analysis Approach 495
15.2.3 Random Vibration Analysis 496
15.2.4 Response Spectrum Analysis 496
15.2.4.1 Method Description 496
15.2.4.2 Modal Combination Techniques for Response Spectrum Analysis 497
15.2.4.3 Spatial/Directional Combination of the Ground Motion Excitations and Structural Response 500
15.2.4.4 Limitations of the Response Spectrum Analysis 502
15.2.4.5 Determination the Equivalent Quasi-Static Acceleration for Offshore Platform Structures 503
15.2.5 Non-linear Static Pushover Analysis 505
15.2.5.1 Method Description 505
15.2.5.2 Procedure for Executing a Pushover Analysis 505
15.2.5.3 Lateral Load Patterns 507
15.2.5.4 Advantage of Non-linear Static Pushover Analysis 510
15.2.5.5 Limitations of Conventional Pushover Analysis 511
15.2.6 Non-linear Dynamic Time Domain Analysis 513
15.2.6.1 Method Description 513
15.2.6.2 Limitations of the Non-linear Dynamic Time Domain Analysis 514
15.2.7 Case Studies 515
15.2.7.1 Case Study 1—Spectrum Analysis of a Jacket Structure 515
15.2.7.2 Case Study 2—Spectrum Versus Time Domain Analysis of a Gravity Based Structure (GBS) Structure and Its Topside 519
15.2.8 Response Difference Between Response Spectrum and Non-linear Dynamic Time Domain Analysis 528
15.3 Selection of Principal Directions in Seismic Analysis 528
15.4 Recently Developed Methods 529
15.4.1 Incremental Dynamic Analysis 529
15.4.1.1 Method Description 530
15.4.1.2 Assign Limit States by Using IDA Curves 531
15.4.2 Endurance Time Analysis 532
15.4.3 Critical Excitation Method 537
15.5 Characteristics of Seismic Responses 539
15.6 Seismic Transient Excited Vibrations 541
15.7 Whipping Effect 543
15.7.1 Introduction 543
15.7.2 Investigation of the Whipping Effect for a Jacket and Topside Structure 544
15.7.3 Investigation of the Whipping Effect for a GBS and Topside Structure 549
15.7.4 Investigation of the Whipping Effect for a Tower-Podium System 550
15.7.5 Documented Observations of Whipping Responses 552
15.7.6 Mitigation of Whipping Response 555
15.8 Influences from Structures’ Orientations 556
15.9 Remarks on Modeling of Material Properties for Seismic Analysis 557
References 559
16 Sudden Subsidence and Its Assessment 564
16.1 General 564
16.2 Structural Assessment 565
16.2.1 Simplified Static Approach 565
16.2.2 Dynamic Time History Approach 565
16.3 Case Studies 567
16.3.1 Case Study 1: Response of Topside Bridges and Modules Due to Sudden Subsidence 567
16.3.2 Case Study 2: Response of a Topside Flare Boom Due to Sudden Subsidence 570
17 Tank Liquid Impact 572
17.1 General 572
17.2 Tank Damages Due to Earthquakes 574
17.3 Calculation of Hydrodynamic Forces Due to Tank Impact 578
17.3.1 Fluid–Tank Interaction in Horizontal Direction 579
17.3.2 Effects of Flexibility of Tank Walls 596
17.3.3 Fluid–Tank Interaction in the Vertical Direction 598
17.3.4 Implementation of Fluid Modeling in Finite Element Analysis 598
17.4 Soil-Tank Interaction 601
17.5 Codes and Standards for Seismic Tank Design 601
References 602
18 Selection of Computer System and Computation Precision 606
18.1 General 606
18.2 Computer System for Improving Numerical Analysis Efficiency 606
18.3 Computation Precision 610
References 611
19 Avoid Dynamic Amplifications 612
19.1 Seismic Design Principles 612
19.2 Stiffness and Mass Distribution 615
19.3 Elevation Control 616
19.4 Dynamic Magnification Due to Torsional Effects 622
19.4.1 Introduction 622
19.4.2 Mitigation Measures 623
19.4.3 Accounting for Torsional Effects 626
References 627
20 Ductility Through Structural Configuration and Local Detailing 629
20.1 Steel Brace Frames 629
20.2 Buckling-Restrained Brace Frame 637
20.3 Moment Resisting Frame 639
20.4 Shear Walls 641
20.5 Eccentrically Braced Frame 643
20.6 Local Structural Detailing 644
References 647
21 Damping 649
21.1 General 649
21.2 Damping Apparatus 651
21.3 Equivalent Viscous Damping 652
21.4 Relationship Among Various Expressions of Damping 653
21.5 Practical Damping Modeling for Dynamic Analysis … 654
21.5.1 Modal Damping 654
21.5.2 Rayleigh Damping 655
21.5.3 Caughey Damping 656
21.5.4 Non-proportional Damping 657
21.6 Damping Levels for Engineering Structures 658
21.6.1 Material Damping 658
21.6.2 Structural/Slip Damping 659
21.6.3 System Damping 660
21.6.4 Hydro- and Aerodynamic Damping 660
21.6.5 Typical Damping Levels 660
References 662
22 Direct Damping Apparatus 663
22.1 Introduction 663
22.2 Viscous Damper 666
22.2.1 Introduction 666
22.2.2 Advantages and Drawbacks of Viscous Dampers 669
22.2.3 Engineering Applications of Viscous Dampers 670
22.3 Viscous Damping Walls 673
22.4 Cyclic Responses Among Structural Members Made of Elastic, Viscous and Hysteretic (Viscoelastic) Materials 675
22.5 Viscoelastic Damper 677
22.5.1 General 677
22.5.2 Design of Viscoelastic Dampers 679
22.5.3 Engineering Applications of Viscoelastic Dampers 682
22.6 Friction Damper 682
22.6.1 Introduction to Friction Dampers 682
22.6.2 Pall Friction Damper 683
22.6.3 Other Types of Friction Dampers 686
22.6.4 Pros and Cons of Friction Dampers 692
22.6.4.1 Advantages 692
22.6.4.2 Drawbacks 693
22.6.5 Modeling of Friction Dampers 694
22.6.6 Design of Friction Dampers 694
22.6.7 Engineering Applications of Friction Dampers 697
22.7 Yielding Damper 698
22.7.1 General 698
22.7.2 Types of Yielding Dampers 698
22.7.2.1 Eccentrically Braced Frame 698
22.7.2.2 Yielding Steel Cross-Braced System 699
22.7.2.3 Added Damping and Stiffness (ADAS) Dampers 699
22.7.2.4 Seesaw Energy Dissipation System 701
22.7.2.5 Replaceable ShearReplaceable Shear Link Beam Link Beams 702
22.7.2.6 Other Types of Dampers Utilizing Yielding Mechanism 705
22.7.3 Engineering Applications of Yielding Dampers 706
22.8 Lead Dampers 708
22.9 Shape Memory Alloy Dampers 709
22.10 Comparison of Structural Behavior Among Conventional Structures and Structures with Different Damping Apparatus Installed 712
References 714
23 Base and Hanging Isolation System 719
23.1 General 719
23.2 Dynamic Analysis of Base Isolation System 721
23.3 Elastomeric Bearings 723
23.3.1 General 723
23.3.2 Simplified Calculation of Rubber Bearings’ Properties 727
23.3.2.1 Horizontal Stiffness of Rubber Bearings 727
23.3.2.2 Vertical Stiffness of Rubber Bearings 728
23.3.3 Compression and Tension Capacity of Rubber Bearings 730
23.3.4 Determination of Damping in Rubber Bearings 730
23.3.5 Design of Elastomeric Bearings 731
23.3.6 Advantages and Drawbacks 733
23.3.7 Engineering Applications 734
23.3.8 Performance of Elastomeric Bearings During Real Earthquake Events 738
23.4 Sliding Isolation Systems 740
23.4.1 General 740
23.4.2 Determination of Basic Properties for Sliding Isolation Systems 742
23.4.3 Design of Sliding Isolation Systems 744
23.4.4 Advantages and Drawbacks of Sliding Isolation Systems 745
23.4.5 Engineering Applications 746
23.5 Testing of Base Isolation System 749
23.6 Selection and System Comparison Among Conventional Design, Base Isolation and Damping Apparatus 750
23.7 Hanging Isolation System 752
References 754
24 Dynamic Absorber 758
24.1 General 758
24.2 Dynamic Responses Due to the Installation of Dynamic Absorbers 761
24.3 Design Procedure for an Optimized Dynamic Absorber 763
24.4 Practical Considerations for Designing a Dynamic Absorber 765
24.5 Tuned Mass Damper (TMD) 765
24.5.1 General 765
24.5.2 Advantages and Drawbacks of TMDs 768
24.5.2.1 Advantages 768
24.5.2.2 Drawbacks 768
24.5.3 Engineering Applications 768
24.5.4 Research of TMD Systems 773
24.6 Tuned Liquid Damper (TLD) 774
24.6.1 General 774
24.6.2 Calculation of Structural Response with TSDs Installed 776
24.6.3 Research Progress of TLDs 778
24.6.3.1 Effects of TLDs on Mitigating Earthquake and Ocean Wave Induced Responses 778
24.6.3.2 Effects of TLDs’ Baffles or Screens 780
24.6.4 Advantages and Drawbacks of TLDs 782
24.6.4.1 Advantages 782
24.6.4.2 Drawbacks 783
24.6.5 Engineering Applications of TLDs 784
24.7 Multifrequency Dynamic Absorber 787
24.8 Impact Dampers 789
24.8.1 General 789
24.8.2 Advantages and Drawbacks of Impact Dampers 791
24.8.3 Engineering Applications of Impact Dampers 791
References 794
25 Load and Energy Sharing Mechanism 798
25.1 General 798
25.2 Connecting to Adjacent Structures 798
25.3 Lock-up and Shock Transmission Unit 800
References 803
26 Resistance of Non-structural Components 804
References 808
27 Structural Health Monitoring and Earthquake Insurance 809
27.1 Introduction 809
27.2 Vibration-Based SHM 811
27.3 Drone Based Structural Inspections 813
27.4 Inspections by Remotely Unmanned Underwater Vehicles 817
27.5 Earthquake Insurance 819
References 820
28 Control Techniques for External Damping Devices 822
28.1 Introduction 822
28.2 Passive Control Devices 822
28.3 Semi-active and Active Control Devices 824
28.4 Hybrid Control Devices 825
References 825
29 Seismic Rehabilitation for Structures 827
29.1 General 827
29.2 Seismic Rehabilitation Measures 827
29.3 Strengthening of Structures 828
29.4 Reinforcement of Structural Members 834
29.4.1 Local Joint Reinforcement for Tubular Structures 834
29.4.2 Sticking Steel Reinforcement 836
29.4.3 Adding Members, Enlarging Cross Sections and Shortening Spans 836
29.4.4 Retrofitting Using Fiber-Reinforced-Polymer (FRP) 838
29.4.5 Load Sequence Effects Due to the Reinforcement 844
29.4.6 External Pre-stressing Using FRP 845
References 847
Appendix 849
Index 850