Seismic Response of Container Crane under Near-Field and Far-Field Ground Motions

Featured Application This study considers the seismic response of a container crane subjected to near-field and far-field ground motions by a shaking table test on a 1/20 scale crane model. The results are presented focusing on the comparison of the seismic response of the container crane in terms of the maximum internal forces in the landside and seaside legs, the maximum portal drift, and acceleration when subjected to near-field and far-field ground motions. In this study, the seismic response of a container crane under near-field and far-field ground motions was investigated using a shaking table test on a 1/20 scale crane. The 1/20 scale crane was designed and fabricated based on the similitude laws, in which three independent quantities: geometric length, acceleration, and elastic modulus, were used to design the 1/20 scale crane. A series of shaking table tests were conducted at the Seismic Research and Test Center, Pusan National University, Yangsan Campus to evaluate the seismic response of the scale crane under near-field and far-field ground motions. The results show that the near-field ground motions can cause larger internal forces (that is, axial force and two bending moments) in the landside and seaside legs and larger portal drift than the far-field ground motions. The portal drift of the container crane subjected to the near-field ground motions was 43% higher than that of the container crane subjected to the far-field ground motions. Furthermore, when subjected to the near-field ground motion, the bending moment in the crane's portal leg was 37% higher than the bending moment when the crane was subjected to the far-field ground motions.