The document discusses methods for mooring floating structures in Japan, focusing on the use of rubber fenders. It describes four main mooring systems - chains/cables, tension legs, dolphins with fenders, and jackets/piles with fenders. The document then examines forces that affect floating structures like wind, waves, currents and seismic activity. It provides examples of floating structures moored using rubber fenders and discusses fender properties, performance factors, load-deflection characteristics, and variability in reactions forces over time.
Unlocking Growth The Power of Outsourcing for CPA Firms
Floating structures
1. Recent Development of
Floating Structures
in Japan by use of
Rubber Fenders for
Mooring
7 th February 2012
Shigeru UEDA
S. UEDA
2. Design of Mooring System
Methods of Mooring System
1) Chain, Cable ， Anchor ， Sinker
2) Tension Leg
3) Dolphin and Rubber Fenders
4) Jacket ， Pile and Rubber Fenders
External Forces
1) Wind
2) Waves, Wave Drift Force
3) Current
4) Seismic load
Motions and Mooring Forces are calculated
by Numerical Simulation
S. UEDA
3. a) Chain, Cable and Anchor, Sinker b) Tension Legs
c) Dolphin and Fenders d) Jacket, Pile and Fenders
Station Keeping Systems of Floating Structure
S. UEDA UEDA 2007 ７ /09/2007
S. UEDA 2
S. MTEC
S. UEDA
36. 600
500
SUC1000HRH
Re a c tion Fo rc e （ｋ
N)
400
300
200
Deflection against
Steady force 10% Allowable Deflection 35%
100
Rated Deflection
0
0 10 20 30 40 50
Co m pre s s ion St ra in （％）
Figure 3 Load-Deflection Characteristics of Rubber Fender
S. UEDA
37. Creep (Static , Dynamic)
Load-Deflection Characteristics under
Repeated Load
Velocity and Temperature Factor
Deterioration
S. UEDA
38. Repeated compression characteristics of the rubber fender
1.2
1.0
Reaction Force Ratio
0.8
0.6
100H(RH)50%NO.1
0.4 100H(RH)50%NO.2
100H(RH)20%NO.1
100H(RH)20%NO.2
0.2 630H(RH)30%
100H(RH)52.5%
630H(RH)20%
0.0 2 3 4 5 6 7
1 10 10 10 10 10 10 10
Numb e r o f C o mp re s s io n c yc le s
S. UEDA
42. B
Reac B’
tion A C A’
For C’
ce
D’
Compression
Strain
Standard Performance
Compression Strain(%)
S. UEDA Compression Strain
43. Table 5.1 Variation of reaction force against the nominal load-deflection
characteristics
Oil Stockpiling Station (1999) Yume-Mai Bridge (2002)
Manufacturing error 0.90 – 1.10 0.95 – 1.05
Aging 1.00 – 1.05 1.00 – 1.05
Velocity factor 1.00 – 1.10 1.00 – 1.05
Creep The steady load or the mean load shall be less than the reaction
force at 10% strain, and to use the load-deflection characteristics
in consideration of creep.
Repeated 0.8 – 0.9 (at 40% deflection 0.9 – 1.0 (at 20% deflection
compression repeated for more than 10 repeated for more than 10
cycles) cycles)
Inclination Load-deflection characteristics
compression in consideration of the lateral 0.95 – 1.00
force as 10% of the axial force
Temperature factor 0.95 – 1.25 (at 0 – 50oC) 0.95 – 1.25 (at 15 – 45oC)
S. UEDA
