Infrastructure – Flat Jacking and Grout Bags

Description of Project

Hydra Capsule recently completed a complex grout flat jacking operation, with a jacking capability over 1900 tonnes to permanently support the above London Bridge Thameslink Station. The works were based underneath live platforms 14 to 18. The redevelopment of the station is being carried out in phases to maintain the station working for Network Rail.

Over 50 million passengers use London Bridge station each year. By 2018 there will be more trains to more destinations and two-thirds more space for passengers.

Professional Services

Hydra Capsule were appointed to design, manufacture / supply transfusion grout flat jacks and custom-built grout bags (due to unfeasible grouting access), to assist with structural strengthening works.

Hydra Capsule were required to use 160 tonne capacity flat jacks throughout the support steelwork, and in additional, also installed a grout bag at each location. The grout bag was inflated initially to maintain a solid footing gap and then the flat jacks were all inflated and loaded synchronously to preload the installed permanent steelwork.

The operation supported continuous “live” loads throughout the London Bridge Station platform during the works.

Project Features

• Hydra Capsule’s Synchronised Jacking System (1mm accurate)
• 20no. Heavy duty FJ-42 grout flat jacks – design, manufactured (in-house) and supplied
• Real-time and remote monitoring for the jacking and structure
• Grout Bags

Duration of Works

October 2013 to January 2014.