
189
paper, the results of experiments which have condi-
tions similar to conditions of the accident of the M/V
Qingdao and M/V Ocean Asia will be presented.
The Figure 4 and Figure 5 show the experimental
results when the moving model was overtaking sta-
tionary model at the speed of 0.875 m/s and ratio of
canal depth and draft (H/T), respectively, 1.5, 2 and
2.5.
The length between perpendiculars of SITC
Qingdao LBP is 134m. The length of the moving
model in experiment is 4m. So the speed of 9 knots
of the M/V SITC Qingdao equivalent to the model
speed as follows (Cohen 1983):
)s/m(800.0)knots(56.1
134
4
9V
elmod
==×=
(2)
The speed of moving model in the experiment
was 0.875m/s, so it can be considered as same as the
speed of SITC Qingdao when she was overtaking
M/V Ocean Asia.
About the depth of the canal, the rate of draft and
depth of both vessels draft SITC Qingdao and Ocean
Asia were only about H/T = 1.1 ÷ 1.14. From Figure
3 to Figure 5, forces and torque acts on the station-
ery are depended in inversely proportional to the
value of H/T. This leads to the amplitude of forces,
moment acts on the M/V Ocean Asia will be greater
than the value represented on a graph of the case
H/T = 1.5.
Figure 4. Hydrodynamic load CX at equal speed and different
water depths
On the Figure 4, when the distance from SITC
Qingdao to the Ocean Asia was about two lengths of
a vessel (x/l=-1.5) the M/V Ocean Asia was pushed
a bit forward. Since bow SITC Qingdao access to
the stern of M/V Ocean Asia (x/l = -1), the M/V
Ocean Asia was pulled back until the stern of M/V
SITC Quingdao is passed the bow of M/V Ocean
Asia (x/l = 1). During this period, the force got the
maximum value as the bow of M/V SITC Qingdao
passing the bow of M/V Ocean Asia.
The transverse force acting on the hull M/V
Ocean Asia was variable as follows: When the dis-
tance of two vessels is half of vessel’s length (x/l = -
0.5, Fig. 5), the M/V Ocean Asia was pushed toward
the shore. Then, from x/l=0 to x/l=1, M/V Ocean
Asia was pulled to M/V SITC Quingdao. This pull-
ing force was maximum value at the position A on
the Figure 5.
Figure 5. Hydrodynamic load CY at equal speed and different
water depths
At the moment, when the stern of M/V Quingdao
passing the bow of M/V Ocean Asia (x/l=1), the
transverse force was change the direction quickly
and the M/V Ocean Asia was pushed strongly to the
shore.
The Figure 6 shows the moment effects on the
hull of M/V Ocean Asia. Before x/l=0, the moment
changed the direction frequently. It courses the
swaying to the M/V Ocean Asia. When the bow of
SITC Qingdao was passing the bow of Ocean Asia,
the moment rises quickly (point B in Fig. 6). It turns
the bow of Ocean Asia strongly toward to the right
canal.
Figure 6. Hydrodynamic load CN at equal speed and different
water depths
The transverse force and moment acting on the
M/V Ocean Asia peaked almost at the same time as
the bow of SITC Qingdao passing the bow of Ocean
Asia (points A and B in Figure 5 and Figure 6). Un-
der the influence of pulling force and moment, the
M/V Ocean Asia changed her course toward the
right bank of the canal.