Dynamical optimal design and seismic performance of real size container crane with rocking type of vibration isolation system

The container crane of the harbor received the enormous damage in the Hanshin Awaji great earthquake disaster. For the establishment of the earthquake-proof reinforcement quay, there is the container crane with vibration isolation system in practical use. We have proposed the rocking type of vibration isolation system as a new technique instead of the horizontal type of vibration isolation system which have been used in buildings and bridges. The purpose of this study is to examine the performance of the rocking type of vibration isolation system and to present its seismic design method. We analyzed seismic responses for various earthquake waves by three-dimensional FEM analysis, and compared the rocking type of vibration isolation with horizontal type. The result clearly shows that the rocking type of vibration isolation is able to isolate for the twist vibration mode by setting of the damper or using the stabilizer, and the design of the rocking mechanism is easier than horizontal type. In addition we presented the dynamical optimal design method of its damping by using two DOF model.