Photo's and some test results of ship/embankment collapse.

Orientating tests were carried out to examine the possibility
of centrifuge tests for estimating the penetration distance
of a container vessel collapsing with a wall. The tests were related to
the safety of the foundation of the Stone Cutters Bridge (under design) in Hongkong.

Simulation collapse of ship front with sand embankment.
No vertical displacement was allowed.
Centrifuge test is performed at 150g.

Test with smaller ship H=40mm

photo 7 model ship

photo 9 test setup at end of test

load displacement diagram end

The next experiments wil be performed with a scale model of a container ship (made from paper and polyester).

Top view ship

Side view ship

bottom view ship

Dimensions ship: height = 35mm, width hull = 50mm.
Distance from tip to hull = 170 mm.
Some tests have been carried out on Friday 18-05 (100g)

Ship just before start test.

Ship position at end of test.

The following two diagrams show the horizontal and vertical load during penetration. The first diagram shows the beginning of penetration. In the second diagram the tip was pushed into the sand over some distance, in order to visualize the load displacement diagram at larger displacement (the horizontal range of the loading system is only 80 mm).
Interesting phenomenon is that the vertical load (green line) is larger than the horizontal load (blue line). Thanks to the the sharp tip the breaking force looks rather low.
If the load (F)/displacement(s) diagram is known, and the load is scaled in a correct way (square with gravity) than it is easy to calculate in a numerical way the penetration distance of the ship into the embankment.

The basic equations are:
a = F/m (m= mass ship (e.g. 1500MN; maximum break force,F e.g. 150MN)
s(t) = v't + 1/2 at^2 (initial speed e.g. 3 m/s)
v = v'+ at

To Experimental Research in Geotechnics

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This page has last been edited January 2000 by h.allersma@CT.TUDelft.nl.
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