Project Harry Tracy Water Treatment Plant Upgrade
San Bruno, California
Two 12 ft x 12 ft horseshoe shaped tunnels approximately 300 foot long driven via Roadheader.
Completion:
Service Type:
Project Scope:
December 2012
Tunneling
Tunnel, Shaft, Soil Nail Wall, Soldier Piles, and Micropiles
A tunneling project with nail walls
Two 12 ft x 12 ft horseshoe shaped tunnels approximately 300 foot long driven via Roadheader. Ground support consisted of wide flange steel sets with shotcrete lagging. Subsequent to tunnel excavation, 108” diameter welded steel pipes were installed, and the annuluses filled with cellular grout. Multiple permanent sculpted shotcrete soil nail walls were also located throughout the water treatment plant. The largest single wall area is approximately 23,000 square feet and has a maximum retained height of approximately 8 feet. Several micropile foundations were also constructed at the site.
San Francisco Public Utilities Commission, Bernie Mark, Assistant Construction Manager
Kiewit Infrastructure West Co., Clint Cole, Project Manager
Jacobs Associates Glenn, Markland Boyce, Project Engineer
Brett Mainer & Steve McCullough