Case Study

New Victoria – Segmental Shaft Sinking, Manchester

The VJ Donegan Civil Engineering team were approached by Vinci two years before works on the project commenced and developed the operations to enable both the diversion of an existing outfall running across the site, and also provide a new site connection for combined flows into the surrounding network.

Details

Client: Vinci

Services Provided

Tunnelling and Pipejacking

Segmental Shaft Sinking

Civil Engineering Works at New Victoria, Manchester

Scope of Works

The construction of two 3.05m dia segmental shafts over 12m deep
Three timber heading connections excavated in sandstone totalling 55m length
Final connection into a live 1850mm dia brick culvert
The installation of two internal backdrop pipes, turning flows from the existing network into the diversion
Abandonment of a number of existing culverts and manhole chambers.

The solution the company developed solved a number of issues with the original design, including minimising the impact on the local traffic in the heart of the city centre which was crucial to the works be permitted, utilising the new deep chambers to both divert existing flows and take the new flows from the major development.

Therefore this required only a single section application to United Utilities, and by utilising trenchless techniques, this avoided the potential diversion of a large number of services that ruled out any open excavation.

The solution also avoided any requirement to over-pump existing flows which was critical to getting approval from United Utilities and Manchester Council. This reduced the overall construction cost and potential noise pollution to the surrounding areas.

VJ Donegan worked with the civil designer’s expertise to ensure construction drawings reflected the actual works to be undertaken on site, which allowed works to be completed on time and budget to a high quality finish.

Upon completion of the diversion and new outfall works, piling could commence online of the abandoned culvert which was critical to maintaining the overall project programme.