Publications

We contribute technical white papers and magazine articles in a variety of venues. We regularly share our knowledge and experience at maritime conferences in the United States and around the world. Explore our publications by following the links below or select additional topics and conference series at left.

Cranes: Seismic Issues

Seismic Design of Container Cranes October 2010

by Erik Soderberg, Michael Jordan, Jonathan Hsieh, and Yoshi Oritatsu
Presented at the Port and Terminal Technology 2010 Conference in Long Beach, California

Container cranes have evolved to serve ever increasing ship sizes. Today’s typical container cranes are about triple the size of the first cranes, much heavier, and more vulnerable to damage from seismic events. This presentation shows the changes over time that have caused the vulnerability, revisions to design criteria that reduce the vulnerability, the effect of the criteria changes to crane cost and weight, and considerations for existing cranes including some retrofit options and cost estimates.

Presentation

M 8.8 Chile Earthquake Port Damage Assessment March 2010

by Arun Bhimani (contributor: Alberto A. Saez Geraldo of SyS Ingenieros Consultores)
Presented by Arun Bhimani at the TOC Asia 2010 Conference in Shanghai, China

This presentation provides an update on the damage to the Chilean port facilities from the February 27, 2010, M 8.8 earthquake.

Presentation

Seismic Guidelines for Cranes July 2009

by Erik Soderberg, Jonathan Hsieh, and Anna Dix
Presented by Erik Soderberg at TCLEE 2009 Conference

Current large cranes with 100 foot rail gages are much heavier, which results in significantly larger seismic forces in the crane structure. Our studies indicate that many jumbo cranes will be extensively damaged in moderate earthquakes, and many jumbo cranes will be severely damaged, or collapse, in the contingency level design earthquake.

Our presentation suggests some approaches to evaluate what seismic risk is tolerable to existing cranes and some guidelines on what structural characteristics increase or decrease the seismic risk, along with suggested practical retrofit options including strengthening, stiffening, and adding a base isolation mechanism that can limit the seismic forces.

Paper
Presentation

EQ Response – Cement Unloader

Video of linear elastic response of cement unloader on typical West Coast wharf subjected to ground motions transverse to wharf from Port of Los Angeles design earthquake with 475 year mean return interval. Analysis based on no damage to unloader structure.

Video

Seismic Response of Jumbo Container Cranes and Design Recommendations to Limit Damage and Prevent Collapse March 2007

by Erik Soderberg and Michael A. Jordan
Presented by Erik Soderberg at the Ports 2007 Conference

Container cranes have evolved to serve ever increasing ship sizes. Today’s typical container cranes are about triple the size of the first cranes, much heavier, and more vulnerable to damage from seismic events. The seismic vulnerability of these large cranes was only recently recognized as a result of detailed time history analysis.

This presentation discusses what changed to cause the vulnerability, the results of the time history analysis, a physical explanation of the crane-wharf interaction, the inconsistency of seismic design criteria for wharves and cranes, recommended design criteria, and some base isolation and modification concepts.

Paper
Presentation

50′ Gage Crane CLE Closeup

Video

50′ Gage Crane CLE Isometric

Video

100′ Gage Crane CLE Closeup

Video

100′ Gage Crane CLE Isometric

Video