Portsmouth International Port is one of the UK’s busiest municipal ferry ports. In a multi-million pound transformation, a double decked linkspan draw bridge to allow vehicles on and off vessels was to be installed at Berth 4.

As works were due to take place in a working area of the port, a tightly choreographed operation to install and commission the bridge was put into place, ensuring the works had minimal impact on members of the public and port operations.

  • Client
    Portsmouth International Port
  • Principal Contractor
    Freyssinet
  • Designer
    Freyssinet
  • Scope
    Jacking, bearing replacement
Freyssinet was enlisted to carry out jacking and bearing replacement on the roll-on/roll-off ramp at the Ferry Port. This included the supply and installation of a temporary propping and jacking system to enable to removal and replacement of 12 PSC Freyssinet bearings that were installed in 1991.

The scope

Design and installation of temporary works included:

  • Taking into account the loadings of the heavy vehicles using the ramp
  • Making holes in girder’s stiffeners and installing joint gap fillers
  • Welding taper plates to girders in purpose of jacking
  • Dismounting doors and taking down parts of brick walls
  • Levelling floor for temporary supports
  • Building timber cribs – jacks supports
  • Breaking up levelling pads

The jacking and bearing replacement works included:

  • Jacking of the viaduct
  • Dismantling / removal of existing bearings
  • Design, manufacture and installation of 12 Freyssinet Tetron pot bearings

During the de‑jacking of the viaduct, port operations continued uninterrupted, including ferry passenger traffic around the berth. To minimise disruption to the port and the public, Freyssinet carried out the works within segregated, enclosed areas. Close coordination was maintained between Freyssinet’s Site Manager and port officials to carefully plan activities and avoid clashes with critical operations and ferry boarding. As a result, the works were completed successfully within the agreed programme.