Cranes: Wind Issues

Wind Damage to Dockside Cranes: Recent Failures and Recommendations

by Patrick McCarthy.
Presented by Patrick McCarthy at TCLEE 2009 Conference.

Wind-related damage is a threat to most dockside cranes. Typically, damage is localized, but occasionally cranes collapse. Recent crane collapses have been caused by hurricane winds, usually when tie-downs fail, and by lesser winds under operating conditions.

We propose incorporating “ductile link” equalization into tie-down systems as a retrofit method for existing cranes in high-wind areas. We use an economy vs. risk approach to evaluate the need to retrofit existing cranes.

Increasing Hurricane Winds? Dockside Crane Retrofit Recommendations

by Patrick McCarthy, Kenton Lee, Michael Jordan, and Stu Werner.
Presented by Patrick McCarthy at the Ports 2007 Conference.

Studies indicate that the intensity, size, and duration of tropical cyclones (hurricanes and typhoons) are increasing dramatically and may be correlated, at least in part, to increasing ocean surface temperatures. This appears to be a global phenomenon and many scientists predict the trend is not likely to abate any time soon.

This presentation discusses recent trends in hurricane wind loading, a novel new design “ductile link” tie-down system, and an economy vs. risk approach for retrofitting existing structures making comparisons to current approaches for seismic retrofit of buildings. This paper also reviews performance of cranes in the US East and Gulf coasts during recent hurricanes.

Securing Cranes for Storm Winds: Uncertainties and Recommendations

by Patrick McCarthy and Feroze Vazifdar.
Presented by Patrick McCarthy at the Ports 2004 Conference.

Storm wind is one of the few forces that, although considered in dockside container crane design, still causes significant damage—even collapse. Most collapses, however, are usually not caused by an initial failure of the crane structure itself, but rather by failure of the tie-down/stowage pin system securing the crane to the wharf.

This presentation primarily examines the process of calculating corner uplift forces and discusses inherent uncertainties involved. This presentation also examines typical tie-down/stowage pin system designs and design criteria and makes recommendations for improvements.