Case Study

Liverpool Waters, Stanley Dock – Civil Engineering Projects, Liverpool

V J Donegan & Co Ltd were approached by Excalon to provide a solution for laying 2 no. 710mm dia. gas pipes across Great Howard Street.

Due to the high concentration of utility services within Great Howard Street it was deemed that an open-cut technique was inappropriate in the built-up environment with continuous traffic in order to protect the safety of the community.

Drawings indicated that services would be found at varying levels within the road and subsequently, one large diameter tunnel would not be suitable.

Consequently, structural engineers at V J Donegan and Co Ltd proposed a twin pipejack to reduce tunnel diameter, with each gas pipe being threaded through separate tunnels.

Details

Client: Excalon / Vital Energi

Value: £600,000

Services Provided

Tunnelling and Pipejacking

General Civil Engineering

Reinforced Concrete Structures

Image of Liverpool Water civil engineering projects

Fujiclean installation in South Cheshire

Scope of Works

Construct drive pit 6.50m X 6.00m X 5.50m deep using by pre-pilling steel sheet piles on the opposite side of the street to the tobacco warehouse
Construct reception pit 6.50m X 6.00m X 5.50m deep within the site of the Grade II listed tobacco warehouse
Construct insertion trench 14.00m X 3m X 5.5m using pre-driven steel sheet piles to the back of the drive pit to facilitate the insertion of the 2 no. 710mm dia. gas pipes
32.50m long twin 1200mm pipejack systems constructed by tunnelling machine technology incorporating a backactor, from drive pit to reception pit underneath Great Howard Street
Installation of 2 no. 710mm dia. gas pipes at a depth of 5.50m – 6.00m underneath Great Howard Street

V J Donegan and Co Ltd used expertise to provide value to this civil engineering project by keeping the pipejack length to a minimum.

This was achieved by designing the construction of a reception pit that utilised the use of SFA piling so that the pit could be located next to a derelict chimney without undermining its foundations.

This work was completed for a vital role in the new development on the Stanley Dock Tobacco Warehouse infrastructure that is part of the Liverpool Waters regeneration project.