Ship to shore crane subject to earthquake

This paper is concerned the dynamical behaviour of the lifting machine and in particular the ship to shore crane subject to the earthquake. The reason of this work starts at the observation that the components of the crane may be subjected to very high stress and so the earthquake may be very dangerous. There are many phenomena induced by the earthquake like local and global buckling, and overturning moment which may lead to the collapse of the crane components. The paper wants to answer to the question if the earthquake is more dangerous than the normal operating conditions for the ship to shore crane and if the answer is yes, it is very important to know the differences. For this scope, the first step regards the whole design, by the standards, a very big ship to shore crane. The main parameters are: • height=33+15 m; • working load limit=450 kN.
After that, a solid model and subsequent fem analyses were performed in order to verify the safety factors for different load conditions that the crane may be subjected. The next step regards the dynamical analyses like modal analyses for evaluation both the deformation and natural frequencies and both the modal participation factors. The last step concerns the application of specific spectrums of acceleration to simulate a possible earthquake in the Italian region. The results shows that, in this specific case , the actions induce by earthquake are very low.