Dr. Sauer & Partners designed a 1600 x 1200mm temporary works tunnel with traditional squareworks timber support for contractor Dragados and client London Underground at the Bank Station Capacity Upgrade (BSCU) project.
The tunnel, named Rail Delivery Adit forms a connection at the North Tie-in between the current location of the new Northern line Southbound SCL running tunnel and the existing running tunnel to provide access for rail deliveries from the existing tunnel into the new BSCU platform and running tunnel.
The team of Dragados and London Underground started the works at the beginning of the new year and successfully completed the short connection within two weeks. A challenging portion of the temporary tunnel had to be excavated and supported parallel to the operational Northern line running tunnel exposing the existing cast iron segmental lining.
Comprehensive monitoring of the existing tunnels and tracks by Geocisa was essential to control the behaviour and interaction of the new works with the existing structure.
The team celebrated the successful completion with a mini breakthrough into the existing running tunnel by cutting and removing parts of the existing cast iron segments to form the opening through which the rails can be delivered whilst fit out works in the remainder of the new BSCU station continue to progress.
Congratulations to all involved parties.