A satisfactory tunnel design anticipates drainage needs by managing the build up of hydrostatic pressure on the waterproofing layer and by transporting water away in the tunnel invert.
ABG Geosynthetics have developed a range of geocomposite drainage products specifically for tunnel drainage. The Cavidrain® range is a pre-formed cavity drainage system specifically designed to relieve the effects of water penetration from tunnels and is suitable for both remediation and new build. this drainage system can be used in both tunnel walls and tunnel invert drainage and has been specifically developed to provide a highly effective drainage system and mitigate the adverse effects of water on tunnel structures.
The Cavidrain® protector solution provides a free draining layer to collect infiltration water from behind tunnel linings as well as providing protection from physical damage. Cavidrain® Protector acts to minimise the build-up of hydrostatic pressure, thus protecting and enhancing the effectiveness of the waterproofing layer and provides significantly more drainage capacity than traditional geotextile fleece solutions.
Cavidrain® Liner is a combined drainage and waterproofing liner that is welded to form an integral waterproof system. The liner sheets are easily fixed to the smoothed excavated walll and the system is finished with shotcrete.