Page 19 - Marine Structural Design

mi Contents

24.3 Uncertainty Analysis ............................................................................................................... 436
24.3.1 Uncertainty Classification ................................................................................................ 436
24.3.2 Uncertainty Modeling ...................................................................................................... 437
24.4 Selection of Distribution Functions ......................................................................................... 438
24.5 Uncertainty in Ship Structural Design ..................................................................................... 438
24.5.1 General ............................................................................................................................. 438
24.5.2 Uncertainties in Loads Acting on Ships ........................................................................... 439
24.5.3 Uncertainties in Ship Structural Capacity ........................................................................ 440
24.6 References ............................................................................................................................... 441
CHAPTER 25 RELIABILITY OF SHIP STRUCTURES ............................................................. 443
25.1 General ..................................................................................................................................... 443
25.2 Closed Form Method for Hull Girder Reliability .................................................................... 444
25.3 Load Effects and Load Combination ....................................................................................... 445
25.4 Procedure for Reliability Analysis of Ship Structures ............................................................. 448
25.4.1 General ............................................................................................................................. 448
25.4.2 Response Surface Method ................................................................................................ 448
25.5 Time-Variant Reliability Assessment of FPSO Hull Girders .................................................. 450
25.5.1 Load Combination Factors ............................................................................................... 452
25.5.2 Time-Variant Reliability Assessment .............................................................................. 454
25.5.3 Conclusions ...................................................................................................................... 459
25.6 References ............................................................................................................................... 459
CHAPTER 26 RELIABILITY-BASED DESIGN AND CODE CALIBRATION ....................... 463

26.1 General ..................................................................................................................................... 463
26.2 General Design Principles ....................................................................................................... 463
26.2.1 Concept of Safety Factors ................................................................................................ 463
26.2.2 Allowable Stress Design .................................................................................................. 463
26.2.3 Load and Resistance Factored Design ............................................................................. 464
26.2.4 Plastic Design ................................................................................................................... 465
26.2.5 Limit State Design (LSD) ................................................................................................ 465
26.2.6 Life Cycle Cost Design .................................................................................................... 465
26.3 Reliability-Based Design ......................................................................................................... 466
26.3.1 General ............................................................................................................................. 466
26.3.2 Application of Reliability Methods to ASD Format ........................................................ 467
26.4 Reliability-Based Code Calibrations ....................................................................................... 468
26.4.1 General ............................................................................................................................. 468
26.4.2 Code Calibration Principles ............................................................................................. 468
26.4.3 Code Calibration Procedure ............................................................................................. 469
26.4.4 Simple Example of Code Calibration ............................................................................... 469
26.5 Numerical Example for Tubular Structure .............................................................................. 471
26.5.1 Case Description .............................................................................................................. 471
26.5.2 Design Equations ............................................................................................................. 471
26.5.3 Limit State Function (LSF) .............................................................................................. 472
26.5.4 Uncertainty Modeling ...................................................................................................... 473
26.5.5 Target Safely Levels ........................................................................................................ 474
26.5.6 Calibration of Safety Factors ............................................................................................ 475
26.6 Numerical Example for Hull Girder Collapse of FPSOs ......................................................... 476
26.7 References ............................................................................................................................... 479
CHAPTER 27 FATIGUE RELIABILITY ....................................................................................... 481

27.1 Introduction ............................................................................................................................. 481
27.2 Uncertainty in Fatigue Stress Model ....................................................................................... 481