Waterproofing any structure can involve considerable challenges. In the case of tunnels, where water seepage is often a major problem, waterproofing of an exceptionally high standard is required.
As the UK market leader in waterproofing technology, Rock is committed to delivering the most durable, advanced and cost-effective solutions for tunnels built to convey pedestrians and vehicles. To do this, Rock has forged an alliance with Flag-Soprema UK Ltd, a division of the global Soprema Group.
Soprema was established over 100 years ago and today operates production plants worldwide. The company manufactures Flagon, a synthetic membrane that is the principal component of a high performance waterproofing system which has been employed in the building of tunnels across five continents. With regard to structural waterproofing, Rock’s relationship with Flag-Soprema goes back many years. The strength of the partnership means that we have been able to expand our offer to encompass tunnels. We are qualified and authorised to supply and install Flag-Soprema’s tunnel waterproofing technology for projects in the UK.
This is significant, as previously there has been limited availability of British subcontractors able to install waterproofing to tunnels. Our affiliation with Flag-Soprema was therefore welcomed by our clients who for many years had relied on our skill and experience in waterproofing roofs, car parks and vehicle decks. Now, when a project involves the construction of tunnels below ground level, those same clients know that Rock has the resources and capability needed to complete the job successfully.
Essential Features
Due to the difficulties associated with constructing anything underground, a tunnel must have a life expectancy of several decades. Not only will superior waterproofing enhance the tunnel’s safety, but it will also reduce potential future costs in terms of repair and renovation. Flag-Soprema’s synthetic liners have been formulated to meet the specific requirements of underground works, with advantages that include:
• excellent weldability
• softness and flexibility
• great strength, so resists tearing when subjected to mechanical stress
• maintains integrity in the case of structural movements or soil subsidence
• adaptable to irregular substrates
• suitable for installation in humid places
• high electrical resistance
• resistance to static and dynamic puncturing
• resistant to fire, chemicals, micro-organisms and plant roots
• compatible with drinking water
A chief characteristics of Flagon is its ease of application. The sealing of the waterproof membrane can accommodate complex details and particulars, which is essential for the successful performance of the system as a whole.
Signal layer surface
This feature allows the liner to be checked once it is installed. Any surface damage of the liner is immediately shown by the different colour appearing from the surface underneath. It also makes quality tests easier to perform in the post-application stage.
The Flagon 'fail-safe' system
This system, using transparent synthetic material, is an enhancement of the single-layer waterproofing system. With the application of the Flagon protective layer, the seal of the waterproofing system can be monitored throughout its working life. Quality control is therefore made much easier and the waterproofing system can be repaired, even years after its installation, without the need for expensive excavation. The system allows for application onto wet or irregular substrates and is cost-effective in terms of materials and installation time.
Checking of installed membrane (‘signal effect’)
The contrasting colours of the upper and lower surfaces of most Flagon liners allows the integrity of laid membranes to be checked visually. If, during installation, the waterproof membrane has been in any way damaged or abraded, this will be readily apparent as the darker inner layer of the membrane will be exposed. This can then be easily remedied by welding a piece of the same material over the damaged area.
Rock are now capable of delivering the full Flag-Soprema system and associated waterproofing systems
Please contact Rock to learn more about our waterproofing technology for tunnels and our partnership with Flag-Soprema UK Ltd.
