Seismic response of a container crane subjected to ground motions

This study examined the effect of earthquake frequency on the seismic response of a typical modern container crane. A time-history analysis was carried out on the crane using 93 real ground motion records to investigate its behavior. Also, an eigenvalue and a nonlinear pushover analysis were conducted to obtain the dynamic properties and assess the structural performance of the crane, respectively. Three earthquake suites categorized as low-frequency earthquake suite (LFES), intermediate frequency earthquake suite (IFES), and high-frequency earthquake suite (HFES) were considered in this study. The earthquakes were categorized into the three frequency suites based on their peak ground acceleration-to-peak ground velocity ratio (PGA/PGV). By applying the three earthquake suites in the time-history analysis of the crane, drift ratio, internal forces, stresses, and strain were captured to examine its critical seismic response. The results demonstrated the effect of the frequency content on the seismic response of the crane. The LFES was found to cause drift responses averaging 114% and 480% and stress responses averaging 82% and 261%, which were higher than those of IFES and HFES. LFES, IFES, and HFES were found to exact inelastic demands on the crane above the PGA thresholds of 0.34 g, 0.80 g, and 1.99 g, respectively. The LFES was found to cause an uplift response that averaged 468% higher than that of IFES. The uplift caused by the HFES was observed to be inconsequential. Furthermore, it was found that the ground motions with low PGA/PGV ratio values had a larger damage potential on the container crane.