Rabbit netting, galvanized rabbit netting, hot-dipped galvanized rabbit netting – a rabbit net is essentially a wire mesh cage used to contain stones, serving as a fixed mesh structure for stabilizing fill materials. It is a structural approach for riverbank protection and ecological management in modern civil engineering projects. The wire cage is made from woven or welded wire mesh. These structures can be electro-galvanized, hot-dipped galvanized, or hot-dipped galvanized aluminum, with the woven wire boxes available for additional PVC coating. Using hard, weather-resistant stones as fill material, the rabbit nets won't break down quickly due to abrasion in the stone box or cage. Rabbit nets filled with different types of block stones possess distinct characteristics. Polygonal block stones can interlock well, and the stone cages filled with them are less prone to deformation.
Hexagonal Wire Mesh Structure Requirements: The hexagonal wire mesh is mechanically woven from high corrosion-resistant, high-tensile, and ductile low-carbon steel wire (galvanized iron wire) or steel wire coated with PVC. The box-like structure made from this mesh is known as a stone笼box. According to ASTM and EN standards, the diameter of the low-carbon steel wire used varies according to engineering design requirements, generally ranging from 2.0 to 4.0mm. The tensile strength of the hexagonal wire mesh must be no less than 38kg/m2, and the weight of the metallic coating is usually higher than 245g/m2. The diameter of the edge line of the hexagonal wire mesh panel is generally larger than that of the mesh wire. The length of the double twisted section must be no less than 50mm to ensure that the metallic and PVC coatings on the twisted wire are not damaged.
Advantages of stone笼 net structure:
1. The flexible structure can accommodate changes in the slope without being damaged, offering even better safety and stability than rigid structures.
2. High abrasion resistance, capable of withstanding water flow speeds up to 6m/s.
3. The structure is inherently permeable, offering strong tolerance to the natural action and filtration of groundwater. Suspended particles and silt in the water settle in the crevices of the fill stones, which is conducive to the growth of natural vegetation and the gradual restoration of the original ecological environment.
Use of Gabion Mesh:
Gabion mesh is used for slope support, foundation pit support, rock face mesh spraying on mountains, slope vegetation (greening), and isolation barriers for railways and highways. It can also be made into boxes and pads, used for erosion protection of rivers, embankments, and sea dikes, as well as for reservoir and river weir net boxes. Due to its ecological protection characteristics, it is affectionately called ecological mesh and is a structural method for China's water conservancy project protection and ecological environment restoration.
Control and guide rivers and floods
Severe river disasters are caused by the erosion of riverbanks by flowing water, leading to widespread flooding that results in substantial losses of life, property, and soil erosion. Therefore, in addressing these issues, the use of the ecological mesh structure is one of the solutions, providing long-lasting protection for riverbeds and riverbanks.
2. In the construction of the riverbed in the channel canal:
The construction of channels involves the stability of slopes and riverbeds. Therefore, the use of ecological mesh structures, which have been the primary method for transforming numerous natural rivers and excavating artificial channels over the past century, is essential. It effectively protects riverbanks or riverbeds, controls water flow, and prevents water loss, particularly in environmental protection and water quality maintenance. It also has the function of restoring the ecological environment.
3. In terms of revetment and slope protection:
The structure of stone笼mesh is a highly successful example in riverbank protection and slope foot defense, fully utilizing the advantages of ecological mesh and achieving ideal effects that other methods cannot accomplish.
Galvanized Stone笼Mesh Material Classification:
Galvanized Steel Wire: Low-carbon steel wire with diameter 2.0MM-4.0MM, tensile strength not less than 380Mpa, surface protected by hot galvanizing, the thickness of the galvanized layer tailored to customer requirements, galvanizing amount up to 300g/m2 (electro-galvanized zinc coating is only about 10g).
2. Zinc-5% Aluminum-Mixed Rare Earth Alloy Wire (also known as Galfan): This is an emerging new material in the international market, with corrosion resistance up to three times that of traditional pure zinc-plated wire. The wire diameter ranges from 1.0MM to 3.0MM, and the tensile strength is not less than 1380Mpa.
3. Galvanized Steel Wire with PVC Coating: Low-carbon steel wire, with a layer of PVC protective coating applied to its surface, then woven into various规格 of hexagonal mesh.
Zinc-5% Aluminum-Mixed Rare Earth Alloy Wire with PVC Coating: The zinc-5% aluminum-mixed rare earth alloy wire is coated with a layer of PVC for protection, then woven into various specifications of hexagonal mesh.
Hedge mesh demonstrates its protective advantages in hydraulic engineering by:
Ideal ecological construction and restoration functions
The voids within the stone笼 and matting facilitate water flow, promoting natural exchange between water and soil, creating a habitat for aquatic life and microorganisms, thereby enhancing the water body's self-purification capacity and protecting and improving water sources and quality. The voids in the filling material, either artificially laid soil layers or naturally deposited soil, create conditions for greening and vegetation. Even without sowing seeds, plants will naturally grow, achieving optimization, beautification of the environment, and improvement and restoration of the ecological environment.
2. Excellent permeability properties
Retaining walls and slope protection constructed with wire mesh boxes, filled with loose materials, have numerous pores which facilitate the drainage of soil water behind the masonry and in the subsoil beneath the slope. Once surface water infiltrates the soil, it can be quickly drained through the masonry, effectively lowering the groundwater level and reducing the groundwater pressure behind the wall and below the slope. The structure of stone baskets in slope stabilization and debris flow prevention projects helps to reduce the likelihood of wall damage by ensuring timely drainage. Additionally, the wall's excellent deformation capacity can effectively mitigate the impact of sudden external forces.
3. Stable and comprehensive permeability function.
The gabion mesh is a mechanically woven double twisted grid structure. Local damage will not cause the overall integrity of the box to be compromised. The gabion mesh material has a moderate deformation characteristic, connecting the entire project as a whole without the need for seams. Even if uneven settlement occurs, the overall structure will not crack or have serious issues.
4. Simpler construction methods.
The gabion mesh process can be factory-produced as semi-finished products according to design intentions. On the construction site, the assembly and shaping are done according to the design drawings, then laid on prepared slopes or excavated foundation pits to form retaining slopes or constructed into gabion retaining walls. Filling material is added, and the cover mesh is installed to complete. The operation is simple, minimally affected by weather conditions, and suitable for mechanized operations, ensuring both construction quality and speeding up the project progress. During the construction process of a construction unit, affected by the weather, workers originally assigned to build stone masonry retaining walls were transferred to work on the gabion mesh slopes.
5. Landscape Effect
The easy assembly of the stone笼 net structure and the variety of colors offer us a wide range of structural design options, catering to different regional landscape requirements. Combined with grass lawns and flower trees, we present a green retaining wall or slope.
6. Excellent corrosion and durability resistance.
The steel wire used in gabion mesh is coated with hot-dipped aluminum zinc, providing a more stable surface finish that effectively reduces the oxidation of the wire. After being coated with a resin film, it exhibits corrosion resistance, static electricity prevention, aging resistance, and oxidation resistance, significantly extending its service life. Tests have shown that when plastic is soaked in 30% hydrochloric acid solution for 10 days, there is no discoloration or cracking. This indicates that the material is reliable even in highly polluted areas. The lifespan of steel wire coated with a resin film can reach 70 years.
7. Strong resistance to erosion and storm surge.
The gabion mesh structure is highly effective as erosion control or retaining wall projects on rivers with strong water currents. Experimental evidence indicates that the gabion mesh structure's erosion resistance coefficient is twice that of a typical rock pitching protection project. Even if the blocks within the gabion mat are displaced by the water flow, the deformed cage structure achieves a new equilibrium, ensuring overall integrity remains intact. The gabion mesh structure is flexible, with a certain amount of voids in the cage filled with stones or other materials. When waves break against it, the spray is shattered, reducing the impact force of wave pressure. As waves recede, the presence of voids in the cage disrupts the vacuum suction of the waves, further reducing the damage to the protective works. Moreover, the overall structure can self-adjust slightly under the force of waves, effectively preventing cracks from forming in the wall.
Common structure forms of stone笼mesh:
1. Gabion Box - It is a wire mesh box made by cutting and folding heavy-duty hexagonal mesh, typically assembled from 4 pieces of heavy-duty hexagonal mesh. One large hexagonal mesh is folded to form 4 large faces of a rectangular prism, with two small hexagonal pieces at each end and a dividing mesh in the middle. The gabion mesh boxes can also be made into triangular or trapezoidal shapes, and when stacked, these gabion boxes form a dam with the inclined plane on a single plane.
Riprap mesh baskets, often used in hydraulic engineering retaining walls, are constructed from stacked mesh baskets ranging from 0.5 to 1.0 meters in height. These mesh basket retaining walls are primarily used on steep slopes to control mud and rock flows, prevent landslides, and protect the foundations of roads and railways. The reason for using riprap mesh baskets is their unique ecological function. A thin layer of soil applied to the surface of the protective structure allows for vegetation, as the gaps between the stones accommodate soil, promoting root development and creating a favorable ecological environment. Even without applying soil, over time, the gaps between the stones will fill with silt, allowing for the growth of herbaceous plants, forming a natural ecological habitat. After the riprap mesh baskets are produced, they can be bundled and compressed for packaging to save space.
2. Stone笼matting is a heavy-duty hexagonal wire mesh cut and folded into a metal mesh box. The thickness of the stone笼matting ranges from 0.15 to 0.5 meters, significantly smaller than the length and width of the stone笼boxes. The stone笼matting is divided into several cells by single or double separators. To enhance the structural strength of the stone笼matting, the wire diameters at the edges of the mesh plates are relatively thick. Primarily used in river channels, riverbanks, road embankments, and coastal slope protection structures. It not only prevents riverbanks from being eroded by water currents and waves but also achieves a natural convection function between the water body and the soil below the slope, achieving ecological balance. By spreading soil with stone笼matting, green vegetation can be planted, which enhances the landscape greening effect on the slope.
Section 3: Gabion Retaining Walls are constructed by stacking layers of gabion baskets. The components of a gabion retaining wall are filled with stones of similar size within the wire mesh baskets, which creates a certain porosity. Due to the gaps between the stones, soil and water beneath the masonry and slope can be drained, thereby reducing the water level and the ground water pressure behind the wall and beneath the slope. Prompt drainage minimizes the likelihood of the retaining wall being damaged, significantly extending its lifespan. Additionally, the wall baskets are made of wire mesh, allowing for some deformation. Moreover, the stones can slide against each other, enhancing the wall's ability to withstand sudden external forces.
IV. Roadstone笼网, available in two types: One type is for road protection, such as building a retaining wall with stone笼网boxes on the road side to resist floods and safeguard the road; another type is for reinforcing the subgrade with stone笼nets made of stone笼网boxes. The other type involves placing heavy-duty hexagonal mesh during road construction on the subgrade or when pouring cement for the road surface, serving as reinforcing mesh within the cement to prevent cracking.
Five. Stone笼Rolls, woven into rolls of 30 to 50 meters, are directly laid on slopes for slope protection, preventing soil and water erosion, rock falls. They can also be used for slope support, foundation pit support, rock surface mesh spray, slope vegetation (greening), isolation barriers for railways and expressways, and protective measures against erosion for rivers, embankments, and sea dikes.
Operation of Stone笼 Mesh:
1. Operation of gabion mesh sinking, first involves sinking the gabion mesh woven from wire. It can also be electroplated and coated with PVC (polyvinyl chloride), and PVC gabion mesh sinking can also be used for revetment and toe protection.
2. Stone Boxes (Cage Boxes). Grid-style stone cages are more flexible than welded ones, thus their performance in adapting to settlement and load is different. Although filling with stone materials requires careful attention to ensure dense packing, it is sometimes believed that rigid stone boxes are easier to fill. For non-standard shapes, such as bends or areas where significant settlement may occur, these structures are preferred when woven wire or polymer grid shapes can deform without losing strength.
3. The internal filling of stone笼 mesh is composed of weather-resistant, hard stones that won't quickly break due to abrasion in stone boxes or stone笼 arrays. Stone笼 mesh filled with different types of cobblestones exhibits various characteristics. The angular cobblestones can interlock well with each other, resulting in a stone笼 that is less prone to deformation. Thus, it is more effective in large retaining walls resistant to shearing than round stones, and also benefits the connection of the stone笼. The general size of the filling is 1.5 times the average mesh size. Individual cobblestones are not less than the standard mesh size (typically used woven stone笼 sizes are 60mm x 80mm to 100mm x 120mm), and generally not larger than 200mm in standard size. For cobblestones placed away from the stone笼's exterior and inside, the size requirements for small cobblestones may sometimes be relaxed.
4. Internal Filling. Mechanical filling is generally faster and cheaper, but it does not offer the same level of control as manual filling. For decorative retaining walls, a good appearance and a dense structure should be achieved. When using either method, the filling material must completely fill the wire mesh baskets. The filling material must be packed well to minimize voids, ensuring good contact between individual stones, packed as tightly as possible, and reducing the likelihood of stone movement within the baskets. Both polygonal and round stones can be packed tightly when the filling material size is within the normal range, and additional soil can be added as needed.
Riprap mesh baskets