Terminal T2B was a new satellite terminal forming part of Heathrow Airport’s Terminal 2, located to the east of the central airport site. During the final construction phase, Balfour Beatty engaged Freyssinet to design a system for the controlled unloading and removal of a temporary bracing beam installed at VCC234.

The temporary brace, approximately 15 m long and 324 mm in diameter, provided critical structural stability during construction of the terminal. Once VCC234 was completed and fully integrated into the permanent works, the brace became redundant and was removed to allow construction of the perimeter access road.

  • Client
    Heathrow Airport Limited
  • Principal Contractor
    Balfour Beatty
  • Work commenced
    August 2018
During the final construction phase of Terminal T2B, a new satellite extension of Heathrow Airport’s Terminal 2, Balfour Beatty engaged Freyssinet provide a temporary works design solution for safely unloading and removing a bracing beam.

The design

Freyssinet’s design solution for the safe unloading and removal of the brace took into account the requirements of the project, including the need to be adaptable, as depending on the weather/live loading conditions the brace could be in tension or compression. The design also allowed for the unloading operation to be halted at any moment and the building left in a safe state in the event of any emergency.

Freyssinet’s final design could accept up to ~100tonnes load in either tension or compression, and from a health and safety perspective, the method eliminated the need for hot works in the airside environment. The solution also satisfied further requirements including:

  • Control – ability to release in small (1mm) increments
  • Ability to monitor loads during release
  • Ability to quickly stop works and mechanically lock system (potentially for weeks)
  • Mechanical safety backup and ability to replace jacks in case of hydraulic issues
  • Minimum impact/damage to existing/permanent infrastructure

The installation

Freyssinet was subsequently appointed to undertake specialist design, supply and installation of the bracing removal system for the temporary bracing installed at the terminal. The sequence of the works included:

  • Temporary works design for the cutting of the CHS brace at Heathrow Airport Terminal 2B
  • Preparation
  • Installation of Exoleaf® jackets
  • Installation of clamps
  • Pre-stressing of Freyssibar M56 HTSR+ bars
  • Installation of transfer structure
  • Jacking and load removal
  • Cutting of bracing beam
  • Removal of clamp and brace
  • Removal of main connection steelwork and jacket

Works took place airside at Heathrow Terminal 2B, secured by UK Border Control. Due to the complex working environment and strict security measures in place, operations and the logistical organisation of all materials, equipment and staff needed to be carefully managed. This included:

  • The strategic delivery of materials to Heathrow distribution centre for inspection and inventory logging.
  • Any plant and equipment could only be hired from ‘airside approved’ suppliers.
  • Site personnel required temporary airside passes, which needed to be renewed each week.
  • Site personnel were required to go through airport security each day and were escorted at all times.

Close collaboration with all stakeholders, supported by thorough planning, ensured the brace was removed safely and the technically challenging project was delivered successfully.