Title Page
Abstract
Contents
List of symbols 12
1. Introduction 13
1.1. Background 13
1.1.1. Composite Material Properties and Applications in the Shipbuilding Industry 13
1.1.2. General Characteristics of GFRP Composite Hull Plates 17
1.1.3. Limitations of Composite Hull Structure Design according to Rules and Need for Research 20
1.2. Literature Review 25
1.2.1. Research Trends on Composite Ship Design 25
1.2.2. Analysis of the Method for Determining Composite Mechanical Properties of the Revised ISO International Standard 29
1.2.3. Research Trends Related to Composite Material Properties 32
1.2.4. Relevance and Differentiation between This Study and Previous Studies 45
1.3. Research Contents 47
2. Experimental Procedures and Methods 50
2.1. Design and Fabrication of GFRP Hull Plate 50
2.2. Experimental Methods 54
2.2.1. Strength Test for Composite Hull Plate 54
2.2.2. Definition of Fabrication Quality for Composite Hull Plate 55
3. Influence of Combination Type and Gc on Fabrication Quality of Composite Hull Plate 58
3.1. Strength Performance Analysis of Composite Hull Plate 59
3.2. Fabrication Quality of Composite Hull Plate 64
3.3. Analysis of Effect Relationship of Combination Type and Gc on Mechanical Properties of Composite Hull Plate 68
3.3.1. Correlation between Combination Type and Strength Performance 68
3.3.2. Correlation between Combination Type and Strength Performance by Gc Region 74
3.3.3. Fabrication Quality according to Combination Type and Gc 79
4. Proposal of Design Equation for Composite Hull Structure Design Considering Fabrication Quality 87
4.1. Design Equation for Composite Hull Plate according to Design Rules 88
4.2. Improvement of Design Equation for Composite Hull Plate Considering Fabrication Quality 89
5. Verification of Improved Design Equation for Composite Hull Plate 98
5.1. Review of the Existing Design Results of the Example Ship 98
5.2. Effect Analysis of Improved Design Equation for Composite Hull Plate 101
6. Conclusion 109
References 111
攻读博士学位期间科研成果 123
Table 1. Effect of combination type, stacking schedule, fiber orientation on composite mechanical properties in some literature 34
Table 2. Voids effects on composite mechanical properties in some literatures 38
Table 3. Advantages and disadvantages of the main techniques used for composite quality characterization 44
Table 4. Design details of single-material laminates (CSM) 52
Table 5. Design details of combined-material laminates (CSM+WR) 53
Table 6. Pearson's correlation analysis to conform linearity between the covariance (Gc) and the outcome (flexural strength) 71
Table 7. Test for homogeneity of regression slopes using General linear model (total data) 73
Table 8. Summary of basic assumptions of ANCOVA check results 74
Table 9. Summary of the regression model (CSM) 90
Table 10. Regression coefficient estimation for flexural strength model (CSM) 91
Table 11. Pearson's correlation between all the variables (CSM) 91
Table 12. Summary of the model (flexural strength, CSM+WR) 93
Table 13. Regression coefficient estimation for flexural strength model considering Gc & void (CSM+WR) 93
Table 14. Pearson's correlation between all the variables (CSM+WR) 93
Table 15. Improved required thickness estimation formulas considering quality 95
Table 16. Principal particulars of MMU-G52 98
Table 17. Design coefficients of MMU-G52 related to ship design 100
Table 18. Design condition determination of MMU-G52 related to ship design 101
Table 19. Comparison on flexural estimation results based on rule calculation and improved formulas considering fabrication quality 103
Figure 1. Wide application of fiber reinforcement composite materials 14
Figure 2. (a). Composite hull construction by hand lay-up (Boats, 2021); (b). Boat hull mould during resin infusion 18
Figure 3. GFRP hull scantling process based on ISO 12215-5(2008) and classification society rules 20
Figure 4. Variation in laminate flexural strength with Gc as determined by international rules and material tests 22
Figure 5. Inspection samples of GFRP plates with defects. 22
Figure 6. GFRP hull structural laminate-weight optimization algorithm based on International Rules (ISO standard & International society rules) 27
Figure 7. Flexural strength suggested in ISO 12215-5 (2019) compared to ISO 12215-5 (2008) 29
Figure 8. (a). Typical schematic of glass fiber and carbon fiber weaves (CA Composite, 2021; Castro composites, 2021); (b). Typical composite... 33
Figure 9. Defects in fiber-reinforced plastic laminates: (a) Schematic of common lamination defects (Bowkett et al., 2017); (b) X-ray CT image of... 36
Figure 10. Research objective and main thesis of this study 47
Figure 11. Main contents and research methods of this study 49
Figure 12. Typical GFRP composite crafts and fabrication characteristics (raw materials and fabric combination type) 50
Figure 13. GFRP laminate specimens fabricated by hand lay-up method 53
Figure 14. Material test specimens cutting and configurations (Design Gc=0.30) 55
Figure 15. Burn-off test for the combustion of GFRP laminate specimens 56
Figure 16. Burn-off test procedure for GFRP hull laminate structures, according to ASTM D3171 56
Figure 17. Test specimens and example for burn-off test (CSM single material group, Design Gc=0.30) 57
Figure 18. Tensile test results compared to international design rules 60
Figure 19. Flexural test results compared to international design rules 61
Figure 20. Gc measurements from the burn-off test of the GFRP hull plates (single material group) 65
Figure 21. Gc measurements from the burn-off test of the GFRP hull plates (combined material group) 65
Figure 22. Void content measurements from the burn-off test of the GFRP hull plates (single material group) 66
Figure 23. Void content measurements from the burn-off test of the GFRP hull plates (combined material group) 67
Figure 24. Testing the normality of the flexural strength. 69
Figure 25. Verification of homogeneity of variances of flexural strength test results using Levene's test 70
Figure 26. Scatter plots for flexural strength test results (single and combined material group) 71
Figure 27. Correlation and regression for flexural strength test results by normal and high Gc region 77
Figure 28. Significance comparison on combination type on flexural strength by normal and high Gc region 77
Figure 29. Defects in some example specimens of normal and high Gc region 80
Figure 30. Pearson's correlation and regression analysis of void contents for checking linearity and homogeneity of regression slopes 81
Figure 31. Void content results by normal and high Gc region 82
Figure 32. Void content effect on strength performance of hull plate in normal and high Gc 85
Figure 33. 3D surface plots of multiple linear regression results (Flexural strength considering Gc and void content change) 95
Figure 34. Improved hull laminate design process considering the fabrication quality 96
Figure 35. Selected design area with maximum rule required design pressure 99
Figure 36. Design pressure estimation results of bottom plate 100
Figure 37. Effect of improved design formula to hull structure laminate design (single and combined material; normal Gc and high Gc) 104
Figure 38. Raw material weight estimation (single and combined material; normal Gc and high Gc) 106