Preserving engineering heritage

Remodelling of 20 Finsbury Circus was to cause significant load redistribution to its foundations and ground movemnet. Not a big problem usually but when the site is adjacent to a fragile 1874 cut-and-cover tunnel for the world's oldest underground railway, some more detailed study was needed to ensure such heritage was not damaged and the essential transport link kept open.

A detailed 3D FEA model of the building sub-structure and surrounding ground predicted that the old bridge would not suffer any ill effects resulting from the building remodelling and approval for the redevelopment was granted.

Highlights

• Study of site investigation and records for the cut and cover tunnel asset.

• 3D FEA model of building sub-structure and surrounding ground.

• Simulation of existing building load and the load redistribution associated with the remodelling.

• Prediction of strains on old railway tunnel within acceptable limits.

• Planning approval granted.