A-Line North Aerial Structures

Client

Bay Area Rapid Transit (BART)

Completion Date

2013

Location

Oakland, California

Delivery Method

Negotiated

Division

California
Underground

Contract Value

$19 million
BART Earthquake Safety Project

A-Line North Aerial Structures, a project within the BARTs Earthquake Safety Program that emerged in the aftermath of the 1989 Lomo Prieta earthquake to fortify vulnerable segments of the original BART system, ensuring public safety in the event of an earthquake.

The foundation retrofits for 8 miles of the elevated A-Line track and structures from the Oakland Coliseum Station to the Bayfair Station in Hayward. The project retrofit 353 footings, each requiring an average of 1,000 linear feet of vertical drilling. This work requires drilling and bonding approximately 250 dowels per foundation. Additionally, the scope includes a few structural retrofits for concrete walls, bent caps, and catcher blocks. The team also managed the unique challenge produced by the high-grade rebar that was grouted into each footing for the designed concrete cap.

Using an innovative construction technique, the team successfully completed the project one full year early.