SKYWAY T1 FOOTING TRANSPORTProject SummaryFor the foundation of the new single tower self-anchored suspension bridge between Oakland and Yuerba Buena Island, a large steel footing was transported from its construction site in Ingleside, TX, to the installation site in the San Francisco Bay using the cargo barge LUCKY LOGGER. Early February 2007, the 2,100 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, the footing was lowered onto pre-installed grillage structures. These grillage structures were modified after first being used for the E2-Footing transport. After securing of the footing, 2 bundles of tie rods, and 4 bundles of rod sleeves, the loaded barge departed and was towed to Oakland, CA, via the Panama Canal. Upon arrival, the barge was ballasted down to a minimum freeboard and positioned under the catamaran lift vessel. The seafastening shims were cut loose, and the footing was lifted off the barge while the barge was ballasted. Next day, the lift vessel was towed out into the Bay and installed the footing over the piles. Scope of WorkThe project scope included:
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■ | Feasibility check of the selected barge and design optimum quay height for the newly contructed loading dock; |
■ | Prepare preliminary loading procedure, including 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 Ro-Ro ramp, trailer, and grillage loads; |
■ | Design of footing grillage structures and seafastenings, based on the previously used E2 footing grillage structures; |
■ | Design of tie rod and rod sleeves cradles and seafastenings; |
■ | Prepare Panama Canal transit drawings; |
■ | Prepare detailed ballast plans for the lift-off operation; |
■ | Calculate minimum freeboard, hull stresses, and stability during discharging; |
■ | On-site assistance during lift-off operations. |
Seafastening shim for transverse restraint |
Tie rod bundle in cradles secured to grillage |
Barge moved out from under lifted footing |
Footing floated over the piles |