New Crane Arrives at Dutch Harbor

High winds caused the dockside crane at the APL Dutch Harbor terminal in Alaska to collapse in December 2009 and a replacement crane was required. The best option for APL was to modify and transport a late 1980’s vintage MES post-Panamax crane with articulating boom from APL’s Kaohsiung, Taiwan, terminal to Dutch Harbor.  The wharf was also modified to suit the replacement crane. 

APL retained Portek as the contractor to perform the crane modifications.  Portek transported the crane from its original location in Kaohsiung to a nearby wharf where they performed the crane modification work and seafastening installation. In late June, the crane modification work was complete and the crane was loaded on the barge for transport to Dutch Harbor.  Meanwhile, West Construction began work on the wharf modifications at Dutch Harbor.  The crane arrived at Dutch Harbor in August 2010 and should be in service by the end of September 2010.

Liftech provided crane modification engineering that included changing the gage from 80 ft to 50 ft, modifying the tie-downs, and strengthening the crane structure to suit the gage change and conditions at Dutch Harbor.

Liftech’s wharf engineering modifications included new wharf stowage hardware, strengthening and replacing two crane stops, and modifying and replacing tie-down hardware.

 Liftech also assisted Portek with the seafastening scheme and checked the adequacy of the affected wharves for the temporary loads imposed by skidding of the crane on and off the barges.

The Left Coast Lifter is a barge-mounted crane designed to erect the major components of the San Francisco-Oakland Bay Bridge self-anchored suspension span.  The crane was delivered to the Bay Area in 2009 and was quickly put to work constructing the temporary steel falsework in preparation of the tower and deck erection.  

The Left Coast Lifter is owned by the contractors for the new bridge span, American Bridge/Fluor Daniel Joint Venture (ABF), and was fabricated by Shanghai Zhenhua Heavy Industry Co., Ltd. (ZPMC) in Shanghai, China.  The 100 ft wide x 400 ft long barge was fabricated by US Barge LLC in the United States.  Liftech provided structural engineering consulting services to ABF for the crane structure, including technical specifications, design, and fabrication review assistance.  The crane structure design was a collaborative effort by ZPMC, Liftech, and ABF, with ZPMC as the design-build contractor. 

The crane is the largest crane barge on the West Coast.  The boom, the arm of the crane that lifts the loads, is 25 stories tall and can lift 1700 metric tons, equivalent to approximately one thousand automobiles or a container crane at the Port of Oakland. 

We thank the SEAONC selection committee for selecting our project.  We are grateful for the opportunity to contribute to this exciting project and enjoyed collaborating with the team of American and Chinese engineers.  The credit goes to everyone who contributed to the success of this project. 

Project Poster

Anna had her first experience as a conference speaker, presenting two Liftech papers.  “Extreme Loading of Wharf Crane Girders” is about wharf crane girders subject to extreme loads, their expected performance, and which loads should be considered in the girder design.  “Container Crane Recycling: Upgrade and Relocation” discusses reasons for reusing cranes and considerations for upgrading and relocating existing cranes.

The two papers and presentations are now available on our website.

A damaged pier at McNear’s Beach Park in Marin, California, was repaired by replacing portions with new structure.  The new structure was designed to meet current seismic design criteria.  This required a high performance pile-to-pile cap connection.   The high performance connection was designed using a fiber reinforced bearing pad, isolating the sides of the embedded pile, and unbonding the dowels for 24 inches of length. 

The high performance pile-to-pile cap connection used for this project added little additional cost to the project and significantly improved the seismic performance of the pile connection and the entire structure.  Testing by the University of Washington has shown that these connections perform significantly better during seismic loading than a classical pile connection.  We expect little damage at the pile connection during the design earthquake load.

Read Erik Soderberg’s paper on high performance pile connections.

High Performance Pile Connection

The presentation on “Contain Crane Recycling: Upgrades and Relocation” will be presented on April 28, 2010, from 10:30 to 12 during the Port Infrastructure: Novel Approaches session.

The presentation on “Extreme Loading of Wharf Crane Girders” will be presented on April 27, 2010, between 3:15 and 4:45 during the Port Infrastructure: Automation and New Technology session.

The tour began at the technology center, where we learned how computers help determine the optimum mold arrangement to reduce shrinkage voids and residual stresses for the various casting geometries.  The technology office looked like a regular engineering office with computers and ergonomically arranged work stations, but one thing was very different–every minute or so the ground shook several times as the operators at the forge next door dropped their giant hammers.

After an interesting demonstration of the software, we headed over to the hot part of the foundry, the electric arc furnace.  We were lucky enough to witness a batch being heated and then poured into a large ladle for transport to the molds.  After the appropriate quantities of materials are weighed and put into the furnace, the mix is heated by two 6 to 8-inch diameter electrodes.  The sound of the mix heating is exactly as you would expect, the sound of viscous liquid sloshing with undertones of buzzing electricity.

We also toured the area where they make the molds.  The molds are primarily made of sand and resin, and are formed from a wooden pattern.  The patterns, which are outsourced, are quite pricey at several thousand dollars per pattern.

The second half of the tour was all about finishing the castings.  We learned about form removal, cleaning, visual inspection, dye penetrant and ultrasonic testing, cutting, and welding.  We also caught a glimpse of some of the finished products ready to export to clients.  The size of castings fabricated at the Berkeley foundry range in weight from a few ounces to several thousand pounds.

You can learn more about Pacific Steel at http://www.pacificsteel.com/.

Thanks for a great experience, Pacific Steel!