From within the Tunnel

The station is located in central London between Tottenham Court Road and Liverpool Street Crossrail (CRL) Stations. Constructed in the geologically most complex area in the whole of CRL, an optimised geotechnical and SCL tunnel design was implemented, which resulted in significant time and cost benefits for the project. Using a dynamic 3D geological model in conjunction with SCL tunnelling represented a key element of the geotechnical risk management framework.

Devil's Slide is located south of the City of Pacifica in California along the coastal road of Highway 1. Landslides and grade subsidence in the Devil's Slide area along Route 1 have led to the road being closed for extended periods causing significant economic loss to the surrounding communities. The solution: Construct a tunnel through the mountain to bypass the dangers and reoccurring problems. Construction of 1250m twin tunnels, 9m wide, 6.8m high using Sequential Excavation Method (SEM). Additionally, drill and blast and roadheader excavation through weathered rock utilised.

The Beacon Hill Tunnels and Station are part of the 22.5km initial segment of the Sound Transit Central Link Light Rail Line that will establish a high capacity commuter connection from downtown Seattle to Tacoma. The 1300m running tunnel under Beacon Hill will be mined by Earth Pressure Balance Machine (EPB), while the deep mined Station will be constructed using slurry walls and the New Austrian Tunneling Method (NATM), referred to as Sequential Excavation Method (SEM) for this project.