Transportation and Infrastructure
Metro BLOC Tunnel
Metro BLOC Tunnel supports Cefali & Associates positioning around transit-adjacent work, constrained underground construction, and constructability.
Project context
Project profile for Metro BLOC Tunnel, supporting transit-adjacent underground construction and constructability-focused engineering.
The Metro BLOC Tunnel connects riders in Metro 7th Street Station directly to the shops and restaurants of the BLOC complex in Downtown Los Angeles.
Cefali helped determine how the connection could be made while the active roadway and public stairway above remained undisturbed.
A system of beams and columns was designed to be installed as excavation progressed from the BLOC toward the station. Before wall removal, a grout tubing system improved ground conditions to prevent caving.
The work involved confined spaces, access restrictions, fumes that prevented welding, low overhead, and multiple bolted splices in beams and columns. The system also had to stay clear of the permanent concrete passage for the final condition.
Related services
Tunnel and shaft structural design, Earth retention systems, Structural design and coordination
- Connection between a Metro station and a private development in Downtown Los Angeles
- Work coordinated around active roadway and public stairway conditions above
- Sequenced underground structural work with constrained access and low overhead
Project images
