An Out-of-Plane Bending Fatigue Assessment Approach for Offshore Mooring Chains Considering the Real-Time Updating of Interlink Bending Stiffness
Abstract
:1. Introduction
2. The Model for a Semi-Submersible Platform
2.1. The Floating Platform and Mooring System
2.2. Hydrodynamic Parameters
2.3. Environment Conditions
2.4. Finite-Element Model
3. Implementation and Validation of MeCAP-Fatigue
3.1. MeCAP-Fatigue for TT and OPB Combined Fatigue Assessment
3.2. Validation of the MeCAP Code
3.3. Real-Time Updating Approach for Interlink Bending Stiffness in MeCAP
4. Numerical Implementation
4.1. Main Procedure for OPB Combined Fatigue Assessment
4.2. Time-Step Selection Principle
4.3. Extraction and Computation of Interlink Angles
4.4. Combined Stress and Fatigue Damage
4.4.1. Stress Concentration Factors (SCFs)
4.4.2. Combined Stress
4.4.3. S-N Curve for Combined Fatigue
5. Results and Discussion
5.1. Effect of Interlink Stiffness on the Fatigue
5.1.1. Comparison of Zero and Time-Varying Interlink Stiffness
5.1.2. Constant Interlink Stiffness and Time-Varying Interlink Stiffness
5.2. Discussion on Pure TT Fatigue and Combined Fatigue Damage
5.3. Influence of Wind and Current on the Fatigue
6. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Appendix A
Case No. | Direction | Hs (m) | Tp (s) | WS 1 h (m/s) | Vc Surf (m/s) | Probability |
---|---|---|---|---|---|---|
1 | NN | 1.5 | 7.7 | 6.5 | 0.38 | 0.77320% |
2 | NN | 2.5 | 8.8 | 8.9 | 0.49 | 0.28073% |
3 | NN | 3.5 | 9.5 | 11.4 | 0.6 | 0.15456% |
4 | NN | 4.5 | 10.1 | 13.8 | 0.71 | 0.07473% |
5 | NN | 5.5 | 10.6 | 16.2 | 0.82 | 0.02146% |
6 | NN | 8.5 | 11.5 | 28 | 1.1 | 0.00056% |
7 | NN | 12 | 13.5 | 35.2 | 1.43 | 0.00008% |
8 | NE | 1.5 | 7.7 | 6.5 | 0.38 | 19.20280% |
9 | NE | 2.5 | 8.8 | 8.9 | 0.49 | 7.04573% |
10 | NE | 3.5 | 9.5 | 11.4 | 0.6 | 3.90135% |
11 | NE | 4.5 | 10.1 | 13.8 | 0.71 | 1.86217% |
12 | NE | 5.5 | 10.6 | 16.2 | 0.82 | 0.48021% |
13 | NE | 6.5 | 11.1 | 18.6 | 0.93 | 0.05442% |
14 | NE | 8.5 | 11.5 | 28 | 1.1 | 0.01412% |
15 | NE | 12 | 13.5 | 35.2 | 1.43 | 0.00209% |
16 | EE | 1.5 | 7.7 | 6.5 | 0.38 | 12.83061% |
17 | EE | 2.5 | 8.8 | 8.9 | 0.49 | 4.65853% |
18 | EE | 3.5 | 9.5 | 11.4 | 0.6 | 2.56466% |
19 | EE | 4.5 | 10.1 | 13.8 | 0.71 | 1.24004% |
20 | EE | 5.5 | 10.6 | 16.2 | 0.82 | 0.31977% |
21 | EE | 8.5 | 11.5 | 28 | 1.1 | 0.04491% |
22 | EE | 12 | 13.5 | 37.9 | 1.57 | 0.00213% |
23 | SE | 1.5 | 7.7 | 6.5 | 0.38 | 8.13501% |
24 | SE | 2.5 | 8.8 | 8.9 | 0.49 | 2.95365% |
25 | SE | 3.5 | 9.5 | 11.4 | 0.6 | 1.62608% |
26 | SE | 4.5 | 10.1 | 13.8 | 0.71 | 0.78622% |
27 | SE | 5.5 | 10.6 | 16.2 | 0.82 | 0.20274% |
28 | SE | 8.5 | 11.5 | 28 | 1.1 | 0.02846% |
29 | SE | 12 | 13.5 | 37.9 | 1.57 | 0.00135% |
30 | SS | 1.5 | 7.7 | 6.5 | 0.38 | 14.68679% |
31 | SS | 2.5 | 8.8 | 8.9 | 0.49 | 5.33247% |
32 | SS | 3.5 | 9.5 | 11.4 | 0.6 | 2.93569% |
33 | SS | 5.5 | 10.6 | 16.2 | 0.82 | 1.78547% |
34 | SS | 8.5 | 11.5 | 28 | 1.1 | 0.05140% |
35 | SS | 12 | 13.5 | 37.9 | 1.57 | 0.00243% |
36 | SW | 1.5 | 7.7 | 6.5 | 0.38 | 2.04144% |
37 | SW | 2.5 | 8.8 | 8.9 | 0.49 | 0.74120% |
38 | SW | 3.5 | 9.5 | 11.4 | 0.6 | 0.40805% |
39 | SW | 5.5 | 10.6 | 16.2 | 0.82 | 0.24817% |
40 | SW | 8.5 | 11.5 | 28 | 1.1 | 0.00713% |
41 | SW | 12 | 13.5 | 35.2 | 1.43 | 0.00034% |
42 | WW | 1.5 | 7.7 | 6.5 | 0.38 | 1.27450% |
43 | WW | 2.5 | 8.8 | 8.9 | 0.49 | 0.46275% |
44 | WW | 3.5 | 9.5 | 11.4 | 0.6 | 0.25476% |
45 | WW | 5.5 | 10.6 | 16.2 | 0.82 | 0.15494% |
46 | WW | 8.5 | 11.5 | 28 | 1.1 | 0.00447% |
47 | WW | 12 | 13.5 | 35.2 | 1.43 | 0.00021% |
48 | NW | 1.5 | 7.7 | 6.5 | 0.38 | 0.20461% |
49 | NW | 3.5 | 9.5 | 11.4 | 0.6 | 0.11518% |
50 | NW | 4.5 | 10.1 | 13.8 | 0.71 | 0.01978% |
51 | NW | 5.5 | 10.6 | 16.2 | 0.82 | 0.00509% |
52 | NW | 6.5 | 11.1 | 18.6 | 0.93 | 0.00059% |
53 | NW | 8.5 | 11.5 | 28 | 1.1 | 0.00014% |
54 | NW | 12 | 13.5 | 35.2 | 1.43 | 0.00003% |
Appendix B
Case 8 | Case 12 | Case 15 | Case 36 | Case 39 | Case 41 | ||
---|---|---|---|---|---|---|---|
Environment | Hs (m) | 1.5 | 5.5 | 12 | 1.5 | 5.5 | 12 |
Dir | NE | NE | NE | SW | SW | SW | |
TT | Zero stiffness | 1.95 × 10−5 | 3.13 × 10−3 | 8.32 × 100 | 3.30 × 10−5 | 2.73 × 10−3 | 9.60 × 100 |
Time-varying stiffness | 1.95 × 10−5 | 3.13 × 10−3 | 8.37 × 100 | 3.27 × 10−5 | 2.69 × 10−3 | 9.58 × 100 | |
Difference | 0.16% | 0.07% | −0.50% | 0.87% | 1.35% | 0.23% | |
Hotspot A | Zero stiffness | 6.22 × 10−5 | 6.25 × 10−3 | 1.97 × 101 | 9.58 × 10−5 | 7.78 × 10−3 | 1.48 × 101 |
Time-varying stiffness | 6.10 × 10−5 | 6.19 × 10−3 | 1.98 × 101 | 9.49 × 10−5 | 7.69 × 10−3 | 1.51 × 101 | |
Difference | 1.92% | 1.02% | −0.50% | 0.96% | 1.10% | −1.87% | |
Hotspot B | Zero stiffness | 4.15 × 10−5 | 1.35 × 10−3 | 3.12 × 100 | 6.45 × 10−5 | 1.80 × 10−3 | 9.04 × 100 |
Time-varying stiffness | 3.13 × 10−5 | 1.52 × 10−3 | 3.04 × 100 | 4.47 × 10−5 | 1.59 × 10−3 | 7.41 × 100 | |
Difference | 32.27% | −11.59% | 2.68% | 44.46% | 13.10% | 22.09% | |
Hotspot C | Zero stiffness | 3.08 × 10−5 | 6.18 × 10−4 | 4.69 × 10−1 | 4.02 × 10−5 | 8.97 × 10−4 | 8.38 × 100 |
Time-varying stiffness | 2.23 × 10−5 | 7.08 × 10−4 | 4.48 × 10−1 | 2.57 × 10−5 | 7.18 × 10−4 | 4.42 × 100 | |
Difference | 37.98% | −12.69% | 4.58% | 56.63% | 24.89% | 89.84% |
Case 8 | Case 12 | Case 15 | Case 36 | Case 39 | Case 41 | ||
---|---|---|---|---|---|---|---|
Environment | Hs (m) | 1.5 | 5.5 | 12 | 1.5 | 5.5 | 12 |
Dir | NE | NE | NE | SW | SW | SW | |
TT | Constant stiffness | 1.95 × 10−5 | 3.13 × 10−3 | 8.44 × 100 | 3.27 × 10−5 | 2.69 × 10−3 | 9.57 × 100 |
Time-varying stiffness | 1.95 × 10−5 | 3.13 × 10−3 | 8.37 × 100 | 3.27 × 10−5 | 2.69 × 10−3 | 9.58 × 100 | |
Difference | −0.01% | 0.04% | 0.90% | −0.05% | −0.05% | −0.05% | |
Hotspot A | Constant stiffness | 6.12 × 10−5 | 6.46 × 10−3 | 1.47 × 101 | 9.46 × 10−5 | 7.70 × 10−3 | 1.44 × 101 |
Time-varying stiffness | 6.10 × 10−5 | 6.19 × 10−3 | 1.98 × 101 | 9.49 × 10−5 | 7.69 × 10−3 | 1.51 × 101 | |
Difference | 0.19% | 4.43% | −25.88% | −0.34% | 0.14% | −4.20% | |
Hotspot B | Constant stiffness | 3.10 × 10−5 | 1.54 × 10−3 | 2.31 × 100 | 4.54 × 10−5 | 1.50 × 10−3 | 7.81 × 100 |
Time-varying stiffness | 3.13 × 10−5 | 1.52 × 10−3 | 3.04 × 100 | 4.47 × 10−5 | 1.59 × 10−3 | 7.41 × 100 | |
Difference | −1.16% | 1.44% | −24.15% | 1.55% | −5.48% | 5.43% | |
Hotspot C | Constant stiffness | 2.27 × 10−5 | 7.66 × 10−4 | 4.02 × 10−1 | 2.63 × 10−5 | 6.91 × 10−4 | 4.65 × 100 |
Time-varying stiffness | 2.23 × 10−5 | 7.08 × 10−4 | 4.48 × 10−1 | 2.57 × 10−5 | 7.18 × 10−4 | 4.42 × 100 | |
Difference | 1.70% | 8.22% | −10.23% | 2.48% | −3.74% | 5.23% |
Appendix C
Case | TT | Hotspot A | Hotspot B | Hotspot C |
---|---|---|---|---|
1 | 1.27 × 10−7 | 1.02 × 10−6 | 1.58 × 10−5 | 1.85 × 10−5 |
2 | 2.90 × 10−7 | 2.15 × 10−6 | 2.35 × 10−5 | 2.88 × 10−5 |
3 | 5.00 × 10−7 | 3.19 × 10−6 | 2.91 × 10−5 | 3.37 × 10−5 |
4 | 4.82 × 10−7 | 3.37 × 10−6 | 2.18 × 10−5 | 2.33 × 10−5 |
5 | 2.73 × 10−7 | 1.77 × 10−6 | 8.53 × 10−6 | 8.69 × 10−6 |
6 | 3.80 × 10−8 | 2.19 × 10−7 | 6.73 × 10−7 | 6.81 × 10−7 |
7 | 1.29 × 10−8 | 6.51 × 10−8 | 1.12 × 10−7 | 1.14 × 10−7 |
8 | 4.06 × 10−6 | 1.17 × 10−5 | 6.02 × 10−6 | 4.29 × 10−6 |
9 | 1.15 × 10−5 | 3.10 × 10−5 | 1.20 × 10−5 | 6.72 × 10−6 |
10 | 2.38 × 10−5 | 6.18 × 10−5 | 1.86 × 10−5 | 9.31 × 10−6 |
11 | 3.11 × 10−5 | 7.15 × 10−5 | 1.74 × 10−5 | 8.05 × 10−6 |
12 | 1.67 × 10−5 | 2.97 × 10−5 | 7.31 × 10−6 | 3.40 × 10−6 |
13 | 2.30 × 10−6 | 5.39 × 10−6 | 1.49 × 10−6 | 6.32 × 10−7 |
14 | 2.63 × 10−6 | 4.54 × 10−6 | 7.06 × 10−7 | 2.63 × 10−7 |
15 | 2.35 × 10−4 | 4.14 × 10−4 | 6.35 × 10−5 | 9.37 × 10−6 |
16 | 4.60 × 10−6 | 1.53 × 10−5 | 1.33 × 10−4 | 1.49 × 10−4 |
17 | 1.26 × 10−5 | 4.13 × 10−5 | 2.03 × 10−4 | 2.20 × 10−4 |
18 | 2.78 × 10−5 | 7.05 × 10−5 | 2.55 × 10−4 | 2.62 × 10−4 |
19 | 2.98 × 10−5 | 7.59 × 10−5 | 1.98 × 10−4 | 1.90 × 10−4 |
20 | 1.37 × 10−5 | 3.09 × 10−5 | 7.12 × 10−5 | 6.50 × 10−5 |
21 | 7.45 × 10−6 | 1.53 × 10−5 | 2.71 × 10−5 | 2.27 × 10−5 |
22 | 9.21 × 10−7 | 1.66 × 10−6 | 1.64 × 10−6 | 1.29 × 10−6 |
23 | 1.62 × 10−6 | 5.51 × 10−6 | 2.86 × 10−6 | 1.89 × 10−6 |
24 | 4.36 × 10−6 | 1.49 × 10−5 | 5.53 × 10−6 | 3.06 × 10−6 |
25 | 8.53 × 10−6 | 2.76 × 10−5 | 7.96 × 10−6 | 4.49 × 10−6 |
26 | 9.83 × 10−6 | 3.10 × 10−5 | 7.23 × 10−6 | 3.36 × 10−6 |
27 | 4.74 × 10−6 | 1.38 × 10−5 | 3.06 × 10−6 | 1.27 × 10−6 |
28 | 6.59 × 10−6 | 7.77 × 10−6 | 1.41 × 10−6 | 7.22 × 10−7 |
29 | 5.78 × 10−5 | 1.10 × 10−4 | 2.44 × 10−5 | 7.27 × 10−6 |
30 | 3.26 × 10−6 | 2.44 × 10−5 | 2.79 × 10−4 | 3.52 × 10−4 |
31 | 1.16 × 10−5 | 6.62 × 10−5 | 4.85 × 10−4 | 5.39 × 10−4 |
32 | 2.51 × 10−5 | 1.18 × 10−4 | 6.13 × 10−4 | 6.93 × 10−4 |
33 | 6.80 × 10−5 | 2.71 × 10−4 | 9.85 × 10−4 | 1.05 × 10−3 |
34 | 3.49 × 10−6 | 1.51 × 10−5 | 4.94 × 10−5 | 5.64 × 10−5 |
35 | 1.88 × 10−7 | 7.95 × 10−7 | 3.73 × 10−6 | 4.33 × 10−6 |
36 | 6.96 × 10−7 | 1.94 × 10−6 | 9.12 × 10−7 | 5.24 × 10−7 |
37 | 2.06 × 10−6 | 5.46 × 10−6 | 1.63 × 10−6 | 9.21 × 10−7 |
38 | 2.97 × 10−6 | 9.20 × 10−6 | 2.59 × 10−6 | 1.27 × 10−6 |
39 | 6.76 × 10−6 | 1.91 × 10−5 | 3.94 × 10−6 | 1.78 × 10−6 |
40 | 5.81 × 10−7 | 1.30 × 10−6 | 2.92 × 10−7 | 1.41 × 10−7 |
41 | 2.84 × 10−5 | 5.12 × 10−5 | 2.52 × 10−5 | 1.50 × 10−5 |
42 | 5.42 × 10−7 | 1.42 × 10−6 | 1.02 × 10−5 | 1.15 × 10−5 |
43 | 1.70 × 10−6 | 3.97 × 10−6 | 1.59 × 10−5 | 1.70 × 10−5 |
44 | 3.21 × 10−6 | 6.52 × 10−6 | 2.03 × 10−5 | 2.16 × 10−5 |
45 | 5.02 × 10−6 | 1.11 × 10−5 | 2.80 × 10−5 | 2.86 × 10−5 |
46 | 5.41 × 10−7 | 9.56 × 10−7 | 1.49 × 10−6 | 1.50 × 10−6 |
47 | 3.97 × 10−8 | 8.21 × 10−8 | 7.69 × 10−8 | 7.28 × 10−8 |
48 | 4.42 × 10−8 | 1.32 × 10−7 | 6.98 × 10−8 | 5.20 × 10−8 |
49 | 7.11 × 10−7 | 1.84 × 10−6 | 5.27 × 10−7 | 2.57 × 10−7 |
50 | 2.78 × 10−7 | 7.45 × 10−7 | 1.72 × 10−7 | 7.67 × 10−8 |
51 | 1.26 × 10−7 | 3.27 × 10−7 | 7.41 × 10−8 | 2.69 × 10−8 |
52 | 2.11 × 10−8 | 5.96 × 10−8 | 1.28 × 10−8 | 4.71 × 10−9 |
53 | 1.32 × 10−8 | 3.76 × 10−8 | 6.34 × 10−9 | 2.50 × 10−9 |
54 | 1.89 × 10−7 | 3.37 × 10−7 | 9.47 × 10−8 | 6.94 × 10−8 |
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Parameter | Unit | Value |
---|---|---|
Overall length | m | 91.5 |
Pontoon | m | 49.5(L) × 21(B) × 9(H) |
Column | m | 21(L) × 21(B) × 59(H) |
Draft | m | 37 |
Displacement | m3 | 105,000 |
Item | Unit | Chain | Polyester |
---|---|---|---|
Nominal diameter | mm | 157.0 | 274.0 |
Wet weight | kg/m | 428.6 | 13.0 |
Tensile stiffness | kN | 1.96 × 106 | 5.4 × 108 |
Minimum break load | kN | 2.36 × 104 | 2.16 × 107 |
Drag coefficient | 2.2 | 1.2 | |
Added mass coefficient | 1.0 | 1.0 |
Parameter | Unit | Value |
---|---|---|
Equivalent length | mm | 628 |
Equivalent diameter | mm | 222.03 |
Young’s modulus | MPa | 206, 800 |
Poisson ratio | - | 0.3 |
Density | t/mm3 | 7.85 × 10−9 |
Mooring Tension (kN) | Surge (m) | Sway (m) | Heave (m) | ||
---|---|---|---|---|---|
Mean Value | DeepC | 2411.926 | 1.931 | 1.368 | 0.011 |
MeCAP | 2411.728 | 1.899 | 1.337 | 0.01 | |
Difference | −0.01% | −1.62% | −2.27% | −1.85% | |
Standard Deviation | DeepC | 62.356 | 1.361 | 1.098 | 0.323 |
MeCAP | 60.907 | 1.392 | 1.134 | 0.312 | |
Difference | 2.32% | −2.28% | −3.26% | 3.42% |
dt (s) | Tension | OPB Angle | IPB Angle | |||
---|---|---|---|---|---|---|
Mean Value | Standard Deviation | Mean Value | Standard Deviation | Mean Value | Standard Deviation | |
0.25 | −0.17% | −0.31% | 1.43% | 95.07% | 0.22% | 61.78% |
0.20 | −0.16% | −0.19% | 0.88% | 90.16% | 0.24% | 38.52% |
0.15 | −0.30% | −1.09% | 0.87% | 16.28% | 0.19% | 8.17% |
0.10 | −0.38% | −1.48% | 0.66% | 0.66% | 0.19% | 0.13% |
Loading Mode | Location | ||
---|---|---|---|
A | B | C | |
TT | 4.48 | 2.08 | 1.04 |
OPB | 0.00 | 1.06 | |
IPB | 1.25 | 0.71 | 1.50 |
Environment | ||
---|---|---|
Free corrosion in seawater | 12.436 | 3 |
Seawater corrosion under cathodic protection | 14.917 | 4 |
Air | 15.117 | 4 |
Location | TT | Hotspot A | Hotspot B | Hotspot C |
---|---|---|---|---|
Fatigue damage | 6.85 × 10−4 | 1.71 × 10−3 | 3.69 × 10−3 | 3.88 × 10−3 |
Fatigue life (years) | 146.0 | 58.3 | 27.1 | 25.8 |
Case 12 | Case 39 | ||
---|---|---|---|
Environment | Hs (m) | 5.5 | 5.5 |
Dir (m) | NE | SW | |
TT | Wave | 3.22 × 10−3 | 3.42 × 10−3 |
Wave and wind | 4.54 × 10−3 | 3.78 × 10−3 | |
Difference | −29.17% | −9.61% | |
Hotspot A | Wave | 6.57 × 10−3 | 8.13 × 10−3 |
Wave and wind | 7.85 × 10−3 | 9.73 × 10−3 | |
Difference | −16.26% | −16.46% | |
Hotspot B | Wave | 1.62 × 10−3 | 1.75 × 10−3 |
Wave and wind | 1.77 × 10−3 | 2.01 × 10−3 | |
Difference | −8.45% | −12.96% | |
Hotspot C | Wave | 7.15 × 10−4 | 6.97 × 10−4 |
Wave and wind | 7.55 × 10−4 | 7.36 × 10−4 | |
Difference | −5.26% | −5.20% |
Wave | Wave and Wind | Difference | ||
---|---|---|---|---|
TT | Mean | 3251.18 | 3423.09 | −5.02% |
Standard deviation | 98.35 | 117.29 | −16.15% | |
Amplitude | 453.18 | 588.68 | −23.02% | |
A | Mean | 406.28 | 427.76 | −5.02% |
Standard deviation | 12.33 | 14.70 | −16.10% | |
Amplitude | 57.80 | 73.95 | −21.83% | |
B | Mean | 230.24 | 241.95 | −4.84% |
Standard deviation | 6.99 | 8.12 | −13.89% | |
Amplitude | 35.79 | 41.31 | −13.36% | |
C | Mean | 141.21 | 148.16 | −4.69% |
Standard deviation | 4.49 | 5.05 | −11.15% | |
Amplitude | 23.98 | 26.14 | −8.27% |
Wave | Wave and Wind | Difference | ||
---|---|---|---|---|
TT | Mean | 3109.75 | 2984.48 | 4.20% |
Standard deviation | 90.47 | 89.17 | 1.46% | |
Amplitude | 439.14 | 465.26 | −5.61% | |
A | Mean | 388.61 | 372.95 | 4.20% |
Standard deviation | 11.33 | 11.19 | 1.31% | |
Amplitude | 55.12 | 58.51 | −5.80% | |
B | Mean | 220.45 | 211.89 | 4.04% |
Standard deviation | 6.55 | 6.57 | −0.42% | |
Amplitude | 34.60 | 35.95 | −3.75% | |
C | Mean | 135.32 | 130.23 | 3.91% |
Standard deviation | 4.27 | 4.35 | −1.96% | |
Amplitude | 23.73 | 25.06 | −5.30% |
Case 12 | Case 39 | ||
---|---|---|---|
Environment | Hs (m) | 5.5 | 5.5 |
Dir | NE | SW | |
TT | Wave | 3.22 × 10−3 | 3.42 × 10−3 |
Wave and current | 2.38 × 10−3 | 2.79 × 10−3 | |
Difference | 35.28% | 22.51% | |
Hotspot A | Wave | 6.57 × 10−3 | 8.13 × 10−3 |
Wave and current | 6.84 × 10−3 | 6.80 × 10−3 | |
Difference | −3.89% | 19.49% | |
Hotspot B | Wave | 1.62 × 10−3 | 1.75 × 10−3 |
Wave and current | 1.59 × 10−3 | 1.63 × 10−3 | |
Difference | 1.77% | 7.80% | |
Hotspot C | Wave | 7.15 × 10−4 | 6.97 × 10−4 |
Wave and current | 6.30 × 10−4 | 7.93 × 10−4 | |
Difference | 13.46% | −12.06% |
Case | Statistic | Name | Wave | Wave and Current | Difference |
---|---|---|---|---|---|
12 | Mean value | Tension (kN) | 3251.2 | 3689.3 | −11.88% |
OPB angle | −6.49 × 10−2 | −5.06 × 10−2 | 28.24% | ||
IPB angle | 5.63 × 10−6 | −3.52 × 10−2 | −100.02% | ||
Standard deviation | Tension (kN) | 98.4 | 79.5 | 23.67% | |
OPB angle | 2.52 × 10−3 | 2.30 × 10−3 | 9.65% | ||
IPB angle | 3.41 × 10−3 | 3.07 × 10−3 | 11.26% | ||
39 | Mean value | Tension (kN) | 3109.8 | 2758.5 | 12.73% |
OPB angle | −6.44 × 10−2 | −7.89 × 10−2 | −18.31% | ||
IPB angle | 3.75 × 10−6 | 4.69 × 10−2 | −99.99% | ||
Standard deviation | Tension (kN) | 90.5 | 57.5 | 57.25% | |
OPB angle | 2.55 × 10−3 | 3.54 × 10−3 | −27.99% | ||
IPB angle | 3.24 × 10−3 | 4.18 × 10−3 | −22.57% |
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Wang, J.; He, C.; Fu, D.; He, K.; Du, J. An Out-of-Plane Bending Fatigue Assessment Approach for Offshore Mooring Chains Considering the Real-Time Updating of Interlink Bending Stiffness. J. Mar. Sci. Eng. 2024, 12, 131. https://doi.org/10.3390/jmse12010131
Wang J, He C, Fu D, He K, Du J. An Out-of-Plane Bending Fatigue Assessment Approach for Offshore Mooring Chains Considering the Real-Time Updating of Interlink Bending Stiffness. Journal of Marine Science and Engineering. 2024; 12(1):131. https://doi.org/10.3390/jmse12010131
Chicago/Turabian StyleWang, Junrong, Chunlei He, Dianfu Fu, Kuang He, and Junfeng Du. 2024. "An Out-of-Plane Bending Fatigue Assessment Approach for Offshore Mooring Chains Considering the Real-Time Updating of Interlink Bending Stiffness" Journal of Marine Science and Engineering 12, no. 1: 131. https://doi.org/10.3390/jmse12010131
APA StyleWang, J., He, C., Fu, D., He, K., & Du, J. (2024). An Out-of-Plane Bending Fatigue Assessment Approach for Offshore Mooring Chains Considering the Real-Time Updating of Interlink Bending Stiffness. Journal of Marine Science and Engineering, 12(1), 131. https://doi.org/10.3390/jmse12010131