Comparative Study of Nonlinear Static and Time-History Analyses of Typical Korean STS Container Cranes

Table 6

Performance levels and limit states proposed by Kosbab [28].

Level of damage/elements	Derailment (DR)	Immediate use (IU)	Structural damage (SD)	Complete collapse (CC)
Whole structures	Derailed without any damage to the structure	Minor structural damage (not significantly impacts its operational capacity). Derailment may or may not have occurred	Extensive damage and will not be suitable for use without major repairs, but not collapse	Local buckling near the portal joints can quickly lead to global instability and eventual collapse
Portal frame	Elastic	Lower limit: elastic. High limit: some minor buckling of hollow sections (within the portal frame or not)	A portal deformation < deformation at max. load capacity up to the point of ultimate ductility	Portal deformation surpasses the estimated point of max. ductility
Overall damage	Derailed	Minor damage	Major damage	Collapse
Limit state in terms of portal drift (for reference)
(i) Crane J100	1.3%	2.0%	3.0%	4.5%
(ii) Crane LD100	—	1.5%	2.0%	3.0%
(iii) Crane LD50	1.5%	1.9%	2.5%	3.5%