Erosion Geomat
Erosion is a natural phenomenon that can cause severe damage to civil infrastructure. To prevent such damage, geosynthetic products can be used to stabilize slopes.
The present study evaluates the performance of different erosion control techniques on slopes at the reservoir margins of two HPPs in Brazil. The degradation of the geomats installed in these sections is evaluated through thermal and mechanical analysis.
3D Geomat
3D Geomat is a new three-dimensional structural geotechnical synthetic material, with good function on slope erosion control, soil conservation and increasing green area and ecological environment. It is mainly used for protecting slopes, riverbanks and other erosion-prone areas to prevent sediment loss, and is also applied in geotechnical projects as soil reinforcement to improve load-bearing capacity and stability. It is suitable for hydraulic applications such as protecting channels and riverbanks, allowing water passage while preventing soil erosion. It is also commonly employed in landfill construction as liners to contain waste materials and to prevent harmful substance leaching. It is also often used in reservoir lining to protect the subsurface and prevent water seepage.
It is made of extruded polypropylene grids that are later bi-oriented and sewn together to form a geomat fabric. It has a void index of more than 90%, which promotes plant growth and helps roots interlock with the soil and the geomat fabric itself. It is available in black or in green to match different slope landforms and climate’s characteristics.
The 3D geomat is a multi-layered mesh with up to four lavers of UV stabilised polyethylene fibres fused together at their intersections. The voids between the fibres trap and hold soil particles, seeds or grass, as well as supporting and anchoring growing roots. Its flexible structure and high void index help reduce the shear forces generated by hydric erosion, and its high stiffness and stability increase its ability to resist damage from soil shear stress.
The installation of the geomat is simple and quick. It is first laid on a prepared soil surface, and then backfilled and compacted. It is then covered with a layer of soil to prevent the Green 3D Geomat geomat from being washed away by rainfall or stream flow.
Polyamide Geomat
Three-dimensional polyamide geomat is a synthetic material that can be used to control erosion processes on slopes. It consists of entangled UV stabilized polyamide monofilament filaments that are fused together at their intersections. It has a high strength-to-weight ratio and is resistant to chemicals, UV, and biodegradation. It is an excellent choice for repairing and strengthening soils, protecting dam embankments, and strengthening slopes of roads and railway embankments. It is also an ideal choice for constructing vegetative barriers, as it can support and speed slope revegetation.
Geomats exercise reliable control of topsoil erosion for slopes with different lengths and gradients, and can be easily installed on a steep graded surface. They also help to reduce the amount of sediment that is carried downstream by floods and surges. This reduces the risk of hurricane overtopping, and allows for greater flexibility in deciding how to best protect a levee from flooding.
The present paper examines the long-term performance of geomats (with and without sack gabion) installed in six margin sections distributed in three experimental units at Hydroelectric Power Plants (HPP). The geomat performance was evaluated over four years of monitoring through a qualitative evaluation matrix and differential bathymetry. The degradation of the geomat wires was Fish farm lining geomembrane assessed in the laboratory through exposure in a UV ageing chamber for 500 and 1000 h. The tensile tests of the geomat wires were also analysed, and their thermal stability was evaluated through thermogravimetry and differential scanning calorimetry.
Multimat P is a pre-seeded three-dimensional geomat, ideally suited for the protection of slopes from surface erosion, supporting and speeding up revegetation on the applied surface. It is used for road and rail embankments, as well as in the protection of slopes of iron and waterways. The Geomat is placed in a vegetative pre-seeded felt, which can be made from natural biodegradable cellulose fibres containing seeds and fertilisers.
Hexagonal Wire Mesh Geomat
Hexagonal wire mesh is flexible, durable, and easy to work with. It is also inexpensive and provides good ventilation, making it an ideal choice for construction and fencing projects. Hexagonal wire mesh is available in a variety of gauges and materials, including galvanized steel and stainless steel. Galvanized hex mesh is particularly rust-resistant and has superior strength. It is also extremely lightweight, making it easy to transport and install.
Hex mesh is used in numerous applications, from safeguarding poultry and livestock to constructing garden trellises and fences. It is also commonly employed in construction to reinforce plastering, masonry, and concrete structures. It can even be molded into sculptures and other creative creations. In addition, hex mesh is also used to create barriers and enclosures for rodents in agriculture and residential settings.
In the field of erosion control, hex mesh is an excellent solution for demanding slope face stabilisation applications. It is designed to withstand abrasion, mechanical damage and ice action. In addition, hex mesh helps to stabilize the soil by reducing its water retention capacity, which leads to faster vegetation colonisation and reduced erosion risks.
Unlike unreinforced erosion geomats, hex mesh is also resistant to UV and other environmental conditions. It is also a cost-effective alternative to traditional materials like steel netting and geogrid. In addition, hex mesh is easily installed and removed without the need for specialist tools.
Hexagonal wire mesh can be reinforced with Maccaferri’s Steelgrid system to produce a multi-functional product that combines 3D geomat and Rockfall Prevention Mesh. This solution is ideal for challenging slope face stabilisation applications, and its mechanical performance exceeds those recommended in EN 10223-3. In addition, the hex mesh allows for hydroseeding and shrub planting, and is suitable at, below, or above the water level, and on rocky soil steep slopes.