Steel-plastic geogrid is a geosynthetic material composed of high-strength steel wire (or steel strand) combined with polyethylene (PE) or polypropylene (PP). It combines the high strength of steel and the corrosion resistance of plastics. It mainly plays the following roles in the project:
1. High-strength reinforcement to improve soil stability
Core mechanism:
The wire in the steel-plastic grating provides tensile strength (usually up to 50-300kN/m), while the plastic wrap protects the wire from corrosion, while friction and engages with the soil through the rough surface texture, transferring the load to a larger range of soil and inhibiting soil deformation.
Application scenarios:
Roadbed engineering: Paved on the base of the roadbed or embankment to enhance the roadbed bearing capacity and reduce uneven settlement (such as soft soil foundation treatment).
Retaining wall and slope reinforcement: As a stretching material, it resists soil side pressure and prevents retaining wall from sliding or slope collapse.
Abutment reinforcement: reduces the differential settlement at the junction of the abutment and the roadbed, and reduces the risk of "jumping off a vehicle at the bridgehead".
2. Disperse loads and reduce structural stress concentration
Principle of action:
The high modulus characteristics of steel-plastic gratings (elastic modulus up to 100-300GPa) enable it to effectively disperse concentrated loads, diffuse a single point of load to a larger area, and reduce the peak internal stress of the soil.
Typical Applications:
Railway track foundation: Paved below the roadbed layer, scattering the impact of train load on the roadbed, extending the service life of the track.
Storage floor and industrial floor: Reinforce under heavy machinery or storage areas to prevent the ground from cracking or sinking.
3. Corrosion resistance and durability, adapt to complex environments
Material Advantages:
The plastic layer (PE/PP) on the surface of the steel wire forms a physical barrier, isolating the contact between moisture, acid and alkali substances and the steel wire. The corrosion resistance is significantly better than that of traditional steel stretchers, and is especially suitable for corrosive environments such as salted soil, swamps, and chemical polluted areas.
Long-term performance:
The plastic layer can also resist ultraviolet aging, with a designed service life of more than 50 years, and is suitable for permanent projects (such as highways and water conservancy hubs).
4. Suppress crack expansion and enhance structural integrity
Anti-crack mechanism:
Laying steel-plastic grilles in asphalt pavement or concrete base layer can inhibit the generation of reflective cracks through stress absorption and diffusion. When the soil is slightly deformed, the tensile performance of the grille can "pull" the soil on both sides of the crack, preventing the crack from further expanding.
Application scenarios:
Old road renovation: lay grilles before adding new road surfaces to reduce the impact of old roadbed cracks on the new surface layer.
Water conservancy channels and embankments: prevent concrete lining cracks caused by uneven settlement of the foundation, and ensure anti-seepage performance.
5. Convenient construction and reduce project costs
Lightweight and flexibility:
The steel and plastic grille is lightweight (about 0.5-2kg/m²), easy to carry and lay, can be constructed manually or mechanically, shortening the construction period.
Economy:
Compared with pure steel stretching or concrete structures, the material cost and construction cost of steel-plastic gratings are lower, and there is no need for complex anti-corrosion treatment, and the comprehensive cost-effectiveness is high.