The Lucky Logger with E2 footings departs Vancouver, WA

Project Summary

For the new single tower self-anchored suspension bridge between Oakland and Yuerba Buena Island, two steel foundation footings plus two connector beams were transported from their construction site in Vancouver, WA, to the installation site in the San Francisco Bay using the cargo barge Lucky Logger. Early September 2006, using a set of 9 Scheuerle self-propelled hydraulic modular trailers, each 1,000 t heavy footing was rolled onto the barge stern over a ramp, while the barge was (de)ballasted to maintain level with the dock. After loading, each footing was lowered onto pre-installed grillage structures. These grillage structures were designed such that they could be re-used with minimum modifications for the T1 footing, to be transported early the following year. After securing of the footings, connector beams, and miscellaneous items, the loaded barge departed and was towed to Oakland, CA.

Upon arrival, the barge was moored for a few weeks in order to complete the pilings. When ready to receive the footings, the barge was ballasted down to a minimum freeboard and the seafastenings were removed. The  barge was then positioned under the catamaran lift vessel, which lifted the footings off the barge while the barge was ballasted. The lift vessel was towed out into the Bay and installed the footings over the piles. This same operation will be repeated later this year for the slightly larger, but much heavier T1 single tower foundation footing. 

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 and grillage loads;

• Design of footing grillage structures and seafastenings;

• Prepare detailed ballast plans for the lift-off operation;

• Calculate minimum freeboard, hull stresses,  and stability during discharging;

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

Project Photographs

The second footing is slowly rolled onto the barge.	Longitudinal stoppers are welded on top of the grillage.	After loading, the barge is relocated to a deep water berth.	The aft footing is lifted off by the catamaran lift vessel.