Ductile Links in Quay Crane Tie-down Systems

by Patrick McCarthy, Erik Soderberg, and Michael Jordan

Severe wind loads have caused the collapse of many cranes. The initial failure usually occurs in the wharf hardware.

If there is more than one tie-down at a crane corner, the crane deflection may cause one tie-down to carry significantly more than its share of the load. If the tie-down system is not ductile, it may fail before the load is shared by the other corner tie-downs. This results in a progressive failure of the tie-downs and crane collapse.

This presentation explains why forces vary between corner tie-downs and introduces the ductile link—one method to improve the reliability of new and existing tie-down systems.