DRILLED AND ROCK SOCKETED PILING

Drilled And Rock Socketed Piling : Branlows remain actively involved in the subsidence marketplace, often involving technically demanding methods of underpinning and foundation piling.  Contracts are predominantly at the larger, more sophisticated end of the market where Branlows are employed to tailor cost-effective solutions to some of the industry's most complex problems.

Northern Counties Housing Association, Chester

Number of piles 70 : Size and length of pile 220mm dia. 23m

In a substantial contract worth over £300,000, Branlows is providing the Northern Counties Housing Association with a solution to a subsidence problem in Chester Previous subsidence had affected the three storey block of flats close to the Northgate Arena, requiring remedial piling measures by others in 1990. Stabilisation work had been undertaken then but the piles had only been installed to one third of the required depth which unfortunately did not arrest the ongoing subsidence.  Needless to say, the original piling contractor is no longer in business and the legal fraternity are now making hay! This is not an isolated case and Branlows looks forward to the day when insurance companies and their professional advisors realise that you only get what you pay for! A highly trained, qualified workforce, in-house chartered engineers and quality systems cost money!  So ten years on, Branlows have been asked to find a solution! Using an overburden drilling system, a permanent steel casing is installed into the sandstone underlying the fill material at depths of up to 26m. A 4m rock socket is then formed prior to the installation of appropriate re-inforcement and grout to complete the pile. Around seventy piles will have a safe working load of 300KN and will interact with an overlying reinforced concrete raft which in turn will support all the load bearing walls of the property.  All the piling work is being carried out from within the building with limited headroom of 2.3m and the contract period is 20 weeks during which time the residents, in 12 apartments, are being re-housed locally! 

Branlows have been appointed principal contractor, responsible for not only the specialist piling and underpinning elements of the project but also the repairs and refurbishment of the superstructure.