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from Figure and Figure . The fender, which is damaged, can be conformed from a time history of
axial force like Figure.

5 CONCLUDING REMARKS
In this study, the eigen frequency characteristics were basically established, and then the nonlinear
three dimension finite element analyzing technique was developed for computing the dynamic
response of a very large floating structure to wave force or combined loads, the case of the existence of
mooring clearance and the case of the geometric changes due to the occurrences of the fender's
breaking were calculated numerically.
Effects of clearance and its size on the deflection of the structure were studied. Main structure is
oscillating like rigid body, and also deflecting elastically.
Under the extreme wave loads, the survivability of the mooring fender was investigated and the path of
breach can be traced by simulating calculation. Therefore this calculating system can be used to the
design of mooring system and the management of VLFS system.
TABLE 5
COLLAPSING BEHAVIOR

11.1213.16
-23.14.1s I I
6.25-7qr) I 95-10.X~) I II7-MXs) I
1.1.;-5.6 I-17.24.25 1-16-9-10 I l875(s)-ll
22 Xr)- 12
19- Is- 17 27256) - -OW i I
-0 M
I Figure 13: Time history of deflection
14.15.1617 --2n.zi.z.n -1.2-3.4 -8.9.10
-1113.18 -24.25 -6-7 SUMVlllb "0 of selected points on main
-11.19 I I I I body
z^ lm.o
Y
-
E 1woo
2 m.0
0.0
0 -m.o
-0 2 -1wo 0
-0 4
I
-0 6
Figure 15: Time history of axial force
Figure 14: Time history of deflection for a selected fender
of selected points on main
structure
References
Hao LIU, Takashi TSUBOGO, Koji MASAOKA, Hiroo OKADA. (1999). a Study on the Horizontal
Deflection Behavior of Very Large Floating Structures Considering Combined Effects with Mooring
Systems, Journal of the Kansai Sociew of Naval Architects, Japan 232, 117-126.
Yoshiyasu WATANABE. (1999). Seismic Behaviors of a Horizontally Elastic VLFS Supported with
Dolphins, Proc., 3rd International Workshop on Very Large Floating Structures (VLFS'99), Honolulu,
USA, 335-342.
Toshiaki HISADA, Hirohisa NOGUCHI. (1995). Theory and Practice in Non-linear Finite Element
Method, Maruzen.