The use of the 20mm Projex Damtec SBM (sub-ballast mat) has proven benefits and technical properties to that of using more traditional methods of culvert protection.

Clients use Projex Damtec SBM on various types of culverts, small and large, as:

  • Projex Damtec SBM is easier to assemble and install then a compacted bedding mix
  • Projex Damtec SBM is cost efficient for the initial construction and the whole of life cost for the culvert(s)
  • Projex Damtec SBM provides superior weight distribution over the whole of the structure
  • Projex Damtec SBM is not affected by soluble salts, organic matter and other deleterious matter/particles
  • Projex Damtec SBM has superior manufactured granular material, which is free of organic matter
  • Projex Damtec SBM is resistant to electrical sensitivity, pH, chloride and sulphate contents
  • Projex Damtec SBM is environmentally friendly, manufactured from recycled rubber
  • Projex Damtec SBM is extremely strong and durable
  • Projex Damtec SBM has high kinetic absorption
  • Projex Damtec SBM has tested and proven properties in insulation for acoustic and vibration and secondary borne vibration to surrounding environs and adjacent structures
  • Projex Damtec SBM provides protection to the sensitive sealing (waterproofing) layer against damage and uneven settlement, which may affect the structure
  • Sub-structure rigidity and long term track geometry stability

The Projex Damtec 20mm Sub-ballast mat (SBM) is extensively used on culverts, bridges and plain rail track in Australia, Europe, North America and various other countries with outstanding results over the whole of life costs. The use of the sub ballast mat ensures superior performance and durability in excess of 50 years.

Multi Cell Culvert Installation, Rockhampton, Queensland:

Multi Cell Culvert covered with 20mm Projex Damtec SBM and joined with Reinforced Projex SBM tape

Multi Cell Culvert covered with 20mm Projex Damtec SBM and joined with Re-Enforced SBM tape

Culverts covered with Geotextile following the installation of the Projex Damtec 20mm SBM

Culverts covered with Geotextile following the installation of the Projex Damtec 20mm SBM

Suitable capping layer applied

Suitable capping layer applied

Single Cell Culvert Installation Rockhampton, Queensland:

Single Cell Culvert

Single Cell Culvert

Single cell culvert covered with 20mm Projex Damtec SBM & Geotextile

Single cell culvert covered with 20mm Projex Damtec SBM & Geotextile

Suitable layer of ballast being applied

Suitable layer of ballast being applied