The capabilities of the CRREL test basin to simulate dynamic ice-structure interaction with scale model tests cover the whole range of structures in question. For bottom-founded structure simulation, a test pile was designed so that its stiffness, natural frequencies and modes and damping could be varied. The ice movement against the pile was arranged to have constant acceleration in order to excite different modes with different ice velocities. The flexibility of drive system caused jerking ice movement with low velocities. Analysis of the recorded ice forces and acceleration include the refinement at measured ice forces by eliminating the response of the measuring system itself using dynamic equilibrium or transfer function approach. The frequency contents and the damping of vibrations are analysed using Fourier signal analyser. Scaling laws are discussed and it is observed that full similitude cannot be achieved for both ice interaction force and pile and ice vibrations. Results thus far show similitude with in-field ice force histograms: both random and saw-tooth like repetitious ice force fluctuations appear. The change from one interaction mode to the other with increasing drive velocities occurs. With high velocities relatively smooth random ice crushing occurs and in some cases natural modes are stable. The greatest energy content of ice forces does not always appear with the natural frequencies of structure. (Author).

In the programme of the symposium was written: "The International Union of Theoretical and Applied Me chanics has taken the initiative to organize the sympo sium. As the name of IUTAM implies, the organization brings forward achievements within the field of theore tical mechanics for application in science and engineer ing. According to the rules of IUTAM that only invited persons can attend, all lecturers and participants have been ap pOinted by the members of the scientific committee. To facilitate contact among the attending persons, it has been decided to restrict the total number to 85 persons including the lecturers. Only one session is planned, making it possible for everybody to attend all lectures. Most scientists and engineers have realized that the knowledge attained by extensive basic research is essen tial in order to solve technological problems. In the process of acquiring this knowledge we often fail to un derstand that scientific progress is only achieved by two main principles: (1) By studying the scientific litera ture and applying or improving the theories in order to predict behaviour and forces correctly, or (2) by re jecting existing theories and developing new ways to cope with the problem, resulting in a more differenti ated and, hopefully, more exact theory. Ice seems to be a simple material, but it is in fact so complex and strange that it is only in the latest dec ades that we have come to know some of the natural laws governing its behaviour.