The majority of leak sealing projects undertaken are undertaken in tunnels although this is not always the case.
Freyssinet have been involved in various projects where this has been undertaken including Glasgow Underground, Connaught tunnel and Crossrail, Hunterston Graphite tunnels and others.
Using various methods including Hydrophillic resins, PU resins and cement grouts Freyssinet have a full range of techniques to stop and control water in tunnels and under slabs.
Specifically Freyssinet carries out injection drilling at positions to the top of cracks in the invert and at side tunnel locations where we are required to stop water ingress. We offer all associated works for this process in cluding drilling and fitting of packers.
The skill of carrying out this work is ensuring that injection locations positioned with the intention of the drilled holes intersecting the crack at the lowest level possible. Typically holes are drilled at an angle of between 45 and 60 degrees and offset approximately 100 – 250mm from the edge of the crack.
All resin components, for example Tam 150, are delivered to site in factory supplied containers in measured quantities. These components are placed in their relevant on site mixing containers (Defined on site as part of the RAMS) and mixed using a forced action mixer.
Upon material cure, injection packers are removed and repaired using mortar plugs and the work is monitored to ensure water ingress is halted.
Freyssinet generally work with the repair of tunnel linings and the utilisation of fixed intermittent positioning of water control liners.
Where required Freyssinet will undertake the installation of full waterproof lining systems using both spray applied liners and membranes.