Project Summary

For the new bridge between Oakland and Yuerba Buena Island, a 200 ft long steel transition box, or  tub, was transported from its construction site in Vancouver, WA, to the installation site in the San Francisco Bay. Early January 2006, using 2 sets of Scheuerle self-propelled hydraulic modular trailers, the 1,500 t heavy tub was slowly rolled onto the barge Lucky Logger, while the barge was (de)ballasted to maintain level with the dock. Once in position, the East bound tub was lowered onto the grillage structures. The tub grillage was designed such that it could be re-used with minimum modifications for the second (West bound) tub, to be transported later this same year. After securing and receipt of a favorable weather forecast, the barge departed and was towed to Oakland, CA.

Upon arrival, the trailers were combined and repositioned under the center of the tub. The barge was towed to site and moored. The tub was lifted free of the grillages and rotated 90 deg. The tub was then lifted off the trailers using computer controlled strand jacks. This same operation will be repeated later this year for the West bound tub. 

Scope of Work

The project scope included:

• Feasibility check of the selected barge;

• Prepare loading procedure, including detailed ballast plans;

• Design optimum stowage arrangement;

• Establish design wave and wind criteria for the tow;

• Stability and barge motion analyses;

• Structural analysis of the barge structure subjected to the trailer loads during loading and rotating;

• Design of internal barge strengthening, tub grillage, and seafastenings;

• Monitor weather forecasts for the tow down to Oakland;

• Calculations of barge draft, trim, and stability during rotating and lifting of the tub;

• On-site assistance during loading, seafastening, and rotation operations.

Project Photographs

East tub safely rolled onto barge, using 2 sets of trailers.	Tub lowered onto grillage/seafastening structure.	Trailers repositioning under tub CG for rotation.	Tub ready for rotation on barge at installation site.