The Maccaferri Ballasted Mattress is a pre-fabricated composite mattress used in underwater applications for filtration, separation, containment and remediation of the sea bed. They are used beneath marine (or river) structures such as breakwaters, scour protection, groynes and the like, or whenever a foundation filter layer is required between the intervention and the sea-bed.
On dry land, a quality geotextile, offering the appropriate filtering (or other physical characteristics) performance and puncture resistance would be simple to install. However, transfer this product to a water environment, and the buoyancy of the textile causes installation problems!
In addition to providing a filter layer the Ballasted Mattress can also provide reinforcement, sealing and polluted sediment remediation properties.
The Maccaferri Ballasted mattresses are designed to provide the required filter performance, be simple to deploy in water and also remain in contact with the sea-bed in order to limit erosion and consequent instability beneath the structure.
Drawing on our extensive geosynthetic portfolio and manufacturing expertise, we use our geotextiles, reinforcement materials and membranes in specific combinations to deliver the performance characteristics required on the project.
The Remediating mattresses are a state-of-the-art approach to the problem of the clean-up of polluted sediments within rivers and estuaries. Dredging and dumping polluted sediments from industrial zones can be incredibly expensive, and disturbing these materials can cause further dispersal downstream. The remediating and sealing functionality of our mattresses can add a valuable tool to help clients fulfil their environmental responsibilities.
Maccaferri Ballasted Mattresses are available in four distinct types:
- Ballasted Filtering Mattress (BFM) – Providing filtering and separation functions. A composite mattress consisting of two geotextiles either side of a reinforced 3D geomat core, which contains the gravel ballast to enable simple deployment under water.
- Remedial Filtering Mattress (RFM) – As the BFM, except that the gravel ballast is mixed with an organoclay/active carbon mix, to provide polluted sediment remediation functionality.
- Ballasted Sealing Mattress (BSM) – Providing underwater waterproofing and containment functions. Similar to the BFM, except that one of the geotextiles is replaced with an impermeable MacLine GCL geomembrane.
- Remedial Sealing Mattress (RSM) – As the BSM, except that the gravel ballast is mixed with an organoclay/active carbon mix, to provide polluted sediment remediation and sealing functionality.