Abstract
The mechanics of the ice load induced by level ice-ship interaction is
analyzed and a mathematical model for the load developed.The ice pressure
which loads the ice wedge originates from the contact process between the ice
edge and the ship hull.The dynamic bending of the ice plate induced by the
contact force determines the ice load.The mechanical constants of the ice form
the basic data for the analysis.The mechanical constants of columnar-grained
sea ice in the northern Baltic are evaluated partly by field tests and partly
by data presented in the literature.The components for the macroscopic failure
criterion of the columnar-grained ice are determined.The two cases: the
three-dimensional and bending stress state are considered separately.A model
for the average ice pressure is formulated.The ice pressure is assumed to
consist of two nominal ice pressures.The effects of the stiffness of the shell
structure and the crushing process are evaluated.The calculated ice pressures
are compared with the measured ones on the full-scale.For this purpose a
special ice pressure gauge was designed.A non-linear dynamic model for the
bending of the ice wedge is presented.The solution is based on the finite
element method.Both the ice wedge and the water under it are modelled.The mode
superposition approach is applied.An ice wedge is analyzed and the results
are compared with data from two different full-scale tests.The first one is a
test with an artificial landing craft bow, the second being the ice load
measurements on board I.B.Sisu.The effects of the speed of a ship and the ice
thickness on the ice loads are investigated.The work on the mechanics of the
ice load does not include all aspects needed for ship design.The aim is to
analyze ice loads in detail and develop a model to determine ice loads based
on ice characteristics and ship particulars.The model forms a basis for future
ice load measurements with which values for ship design can be gathered.
| Original language | English |
|---|---|
| Qualification | Doctor Degree |
| Awarding Institution |
|
| Award date | 4 Nov 1983 |
| Place of Publication | Espoo |
| Publisher | |
| Print ISBNs | 951-38-1843-8 |
| Publication status | Published - 1983 |
| MoE publication type | G4 Doctoral dissertation (monograph) |
Keywords
- ships