TransportationCentral Subway
A 3.1-mile underground extension of the Market Street subway, delivering twin bored tunnels, three underground stations and a cavern beneath an operating city centre.
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Caldecott Improvement Project
A four-bore highway tunnel through the Oakland Hills, including a 3.5-mile bore and seismic retrofit.
Tunnel design, seismic analysis and construction management for a major California highway tunnel.
The scope covered a new parallel bore, cross passages, a drainage and fire-protection system, and seismic resilience features designed for a near-fault site. Complex ventilation and emergency egress design supported a demanding operational and safety case.
Scope of work
- Tunnels & Underground Engineering
- Structural Engineering
- Construction Management
Project facts
- Bores
- 4
- Longest bore
- 3.5 miles
- Seismic
- Near-fault design
- Completion
- 2014
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TransportationCentral Subway project details
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