Construction of foundations for the Skyway Segment of the San Francisco
Oakland Bay Bridge required innovative techniques due to the mass of the
structures being inserted and the unique subsurface of the Bay. Twenty of the
pier structures required large sheet pile cofferdams. Eight other foundations
were installed in open water without cofferdams at the deeper part of the Bay.
This narrative will present the initial planning, as well as the stages of installation,
for each type of foundation.
The first section will discuss foundation constructability modifications made
during the initial planning phases of the project. Considerable effort was
expended by Caltrans, the owner, T.Y. Lin the designer, and KFM
(Kiewit/FCI/Manson) the contractor in modifying the design to assure that
required tolerance would be maintained during the installation of the foundations.
The final section will describe the steps required for installation including: initial
access dredging, installation of cofferdams, preparation required to install the
footing boxes, footing box installation, foundation support pile installation, and
pile to box connections.
Author: Robb L. Swenson, General Construction Company-a Kiewit Company
Publisher: DFI