High-performance, dual density RockBallast® solution (patent pending) with a Terram Limited geotextile. Dual density – high density top layer and low density bottom layer design – ensures that static and dynamic loads from gravel, stone, soil and other covering materials do not result in deterioration of the stone wool fibre material thus helping to provide the exceptional long product life cycle, e.g. as documented by The Technical University of Denmark.
Sophisticated Three-stage Anti-vibration Solution for Ballasted Tracks
Providing for decades of stable, predictable and highest vibration isolation even in the most demanding applications the RockDelta anti-vibration solution for ballasted railway tracks is based on a sophisticated three-stage approach using high-efficiency RockBallast® as the core element.
The solution consists of a unique dual-density sub-ballast mat with; (1) a low-damping, soft resilient layer – designed, tested and manufactured to have an extended lifetime with retained functional performance even under harsh climatic conditions; (2) a force distributing high-density top layer, and finally; (3) the sub ballast mats fibres are being protected from potential impairment by the ballast stones with a geotextile product – with excellent resistance to stretching and tearing – that deforms under the load of the ballast and enables easy replacement of the ballast.
The RockDelta geotextile is a high-quality composite product from Terram Limited comprising two membranes of non-woven geotextile and a load-distributing core. This solution can also be designed to act as a drainage system.
RockDelta Stone Wool: Features, Advantages and Benefits
- Inorganic and inert material with fully retained functional performance throughout entire operational life span
- Outstanding longevity
- Proven track record
- Track anti-vibration experiences since 1974
- Vast report material documenting all aspects of performance
- Resilience virtually unaffected by key environmental factors
- Water, e.g. submersion from flooding
- Sub-freezing temperatures
- Soiling of the ballast bed
- Exposure to sunlight, e.g. pending installation on building site
- Memory-free, e.g. if subjected to flooding and subsequent drying
- High degree of resistance to chemical factors
- Outstanding durability of fibres in acid rain
- Resistant to all naturally occurring soil alkalis and acids
- Long-term practical experiences and theory concur
- High degree of resistance to biological factors
- No nourishment for animals
- Unaffected by fungi and bacteria
- Fire and smoke safe
- Euroclass A2 according to new CEN fire safety standard
- Minimum smoke generation (s1)
- No flaming droplets (d0)
- Inherently withstands more than 1000
- Helps protect track superstructure against frost heave
- Very high Lambda values
- Continues to spread the load down and out from the ballast above
- Helps reduce pressure on sub-grade soil
- Adds to the protection of the sub-grade soil provided by the ballast
- Provides energy absorption from passing trains to prevent shock waves at track joints travelling downwards and possibly damage the sub-grade
Installation of a RockBallast® solution is easy and swift. As installation is performed with easy-to-cut and easy-to-handle mats – and without the use of glue – man power and time required for the installation is minimal at all times, even for a curved track.
Selected Features of a RockBallast® Solution
- Excellent dynamic properties with inherent, first-rate volume compressibility
- Unique dual density design with hard layer upper surface and soft layer core
- Outstanding functional performance under any climatic conditions
- Fully documented specifications based upon exhaustive tests
- Exceptional life-span with virtually no change in functional performance
- Maintenance free solution
- Highly cost-effective
- Short installation time with easy-to-handle mats and no need for gluing
- No functional performance changes at sub-zero temperatures
- All products artificially aged to ensure outstanding long-term stability
- Excellent references
- Designed to work with Terram Limited geotextiles
Terram Limited Geosynthetics
RockDelta is proud to be working closely with UK based Terram Limited whose geo-synthetics products have been successfully used within the rail industry for more than 25 years. Terram Limited’s expansive range of tried and tested non-woven geotextiles are extensively used for separation of the track ballast from the sub-grade and for drainage purposes at the track edge.
Terram Limited’s expansive range of tried-and-tested non-woven geotextiles are extensively used for separation of the track ballast from the sub-grade, for protection of sub-ballast mats and for drainage purposes at the track edge.
The Terram Limited Range of Geosynthetics
Terram PW 1.0 Geotextile
Proven in industry as a drainage separator under ballast.
Terram PW 2.0 Drainage Enhancing Composite
A composite used in wet ground conditions e.g. upward seepage of ground water, bad drainage and flooding.
Terram PW 3.0 Impermeable Membrane Composite
For use over dry, stiff ground initially of adequate bearing capacity but which is prone to 'pumping failure'.
Terram PW 3.1 Impermeable Membrane Drainage Composite
For use in wet conditions e.g. poor drainage and over soils prone to 'pumping' failure.
Terram PW 4.0 Reinforced Composite
Used in conditions to improve track life by stiffening ballast over soft or low bearing capacity ground.
Terram PW 5.0 Radar Detectable Geotextile
Detectable by Ground Probing Radar and hence allows the user to measure the exact depth of ballast above the geotextile.
For more detailed information about the Terram Limited range of geosynthetics please click here.
