There are limited surfaces, such as a conical surface and the approach surface is in the area around airports, setting a limit to the height of buildings. If there is a container wharf in that area, a low-profile container crane shall be employed, which does not include A-frame supporting tension bars and does not raise a boom to be suspended. A low-profile container crane has not been introduced into Japanese ports and its seismic property during earthquakes, which is important to design structures in our country, is unclear; the dynamic response behavior during a level 2 earthquake in Japanese technical standards for port structures has not been clarified. Base isolation mechanisms have been introduced into container cranes in high earthquake-resistance facilities and, however, applicability of base isolation mechanism to a low-profile crane has not been investigated.
Vibration was observed in an actual low-profile container crane, to confirm the vibration characteristics in this research. It was confirmed that natural period of the low-profile crane is shorter than conventional container cranes. Preparing a 1/16 scale model of low-profile crane with reference to the information obtained in the vibration observation, dynamic behavior during large earthquakes and applicability of seismic isolation and boom slides mechanism were examined with model shake table tests. Numerical analysis with a three-dimensional frame model was examined to confirm reproducibility of experimental results such as response acceleration, leg load and seismic isolation displacement.