Geotextile Filter separator – Rail Trackbed applications
TERRAM Hydrotex provides a permanent way and high speed solution for trackbed stability that not only acts as a filter/separator for fine soils, but also removes the requirement for a sand blanket or filter medium.
TERRAM Hydrotex is a nonwoven geocomposite consisting of a central filter media thermally bonded to two opposing needle punched nonwovens Robust Geotextile filter layers, to create a geocomposite with sufficient strength and protection to be durable to the abrasion and point loading of ballast. After 10 years of research and development, this new cost saving technology has now become available globally.
The traditional use of a sand blanket in railway trackbed uses a sub-ballast and/or a graded-sand layer to prevent the upward movement of fine sub-grade particles, while allowing effective drainage and dissipation of pore water pressure. TERRAM Hydrotex offers this solution in one geocomposite.
TERRAM Hydrotex is strong but flexible allowing the composite to conform to the excavated formation, so that no voids exist below the filter media for the development of pockets of slurry resulting in an unstable trackbed.
TERRAM Hydrotex provides true valued engineering. It enables the trackbed to be installed up to 4 x quicker than the standard practice of using sand or sub-ballest.
It also reduces costs to both the clinet and the contractor, reducing material costs, and enabling the track to be handed back 4 times quicker.
- Prevents upwards particle passage smaller than 0.001mm
- Permeable filter, allowing upward and downward water transmission
- Replaces the requirement for a sand blanket or filter medium
- Quickly and easily installed, no specialist plant is required
- Functions under ballast without any reduction in performance
- Approved by Network Rail, SNCP and ProRail
- Residual slurry becomes desiccated as any pore water is dissipated
- Supplied on standard rolls of 3.9m x 25m (other sizes available on request)
TERRAM Hydrotex composite reduces the depth of excavation that would be required with a sand blanket. The result is a decrease in the amount of spoil being taken away for landfill and a reduction of vehicles required to deliver materials.