Residual Stress Analysis and Fatigue Assessment of Welded Steel Structures
نویسنده
چکیده
.............................................................................................................................. .i APPENDED PAPERS ............................................................................................................... ii PAPERS NOT INCLUDED IN THIS THESIS........................................................................ iii DIVISION OF WORK BETWEEN AUTHORS...................................................................... iii CONTENTS.............................................................................................................................. iv INTRODUCTION...................................................................................................................... 1 Background ............................................................................................................................ 1 Research aim .......................................................................................................................... 3 Research approach.................................................................................................................. 3 FATIGUE LIFE ASSESSMENT............................................................................................... 4 Fatigue testing ........................................................................................................................ 5 Effective notch stress method ................................................................................................ 5 Linear elastic fracture mechanics (LEFM)............................................................................. 8 Mixed mode crack growth.................................................................................................... 10 WELD DEFECTS .................................................................................................................... 13 HEAT EFFECTS OF WELDING............................................................................................ 15 Thermal modelling and simulation ...................................................................................... 16 Welding residual stresses ..................................................................................................... 20 Finite element modelling of welding residual stresses......................................................... 20 Material modelling ............................................................................................................... 21 RESIDUAL STRESS MEASUREMENT TECHNIQUES ..................................................... 22 RESIDUAL STRESS EFFECT ON FATIGUE OF WELDS.................................................. 23 Effect of external loading..................................................................................................... 24 Effect on crack propagation ................................................................................................. 25 DISCUSSION .......................................................................................................................... 28 CONCLUSIONS...................................................................................................................... 29 SUGGESTION FOR FUTURE WORK .................................................................................. 30 SUMMARY OF APPENDED PAPERS.................................................................................. 30 REFERENCES......................................................................................................................... 31
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