Bay Trail Pedestrian Bridge

Name: Bay Trail Pedestrian Bridge
Location: South San Francisco
Client: Interstate Grading and Paving
Contract value: $161,000

The project was to build a bridge across a canal in a sensitive coastal area with noise sensitive neighbors, tight access, unregulated construction debris and soft Bay Mud. This bridge provides coastal access for the public. The solution was our soil displacement Tubex piles installed with our smallest low overhead machine.

The site was built with artificial fill over an old shipping channel and was constructed in the late 1960's and early 1970's. The site was formerly owned by a well known excavating contractor who used sand, gravel, clay, rock and various construction debris including large concrete sections and discarded tires to construct the fill. Our Tubex piles easily penetrated this fill without the piles veering off location even though most of the piles were battered.

The fill was placed on soft Bay Mud which can experience circle failures from large loads placed on the mud at the edge of the slope into the canal. Our low overhead machine was light enough to eliminate this hazard.

The California Regional Water Quality Control Board mandated the minimum disturbance to the area so the access was very limited. They also required that any fluids removed from the ground be disposed of in the City of South San Francisco sanitary/industrial sewer. Our Tubex soil displacement pile does not remove soil or water from the ground to eliminate a disposal problem.

The job was designed using micropiles as the sub-foundation, but we were able to do the work for a lower price with our proprietary Tubex piles, and we completed the work on schedule.