High-Tensile Rock Netting for Slope Protection

Standard galvanization is a coating of pure zinc. Galfan is a superior, high-performance coating composed of 95% zinc and 5% aluminum. According to ASTM B117 salt spray tests, Galfan provides 2 to 4 times the corrosion resistance of traditional galvanization of the same thickness. For any long-term rock netting slope protection project, Galfan is the highly recommended minimum standard for a longer design life.

A PVC (Polyvinyl Chloride) coating is added over the Galfan-coated wire for projects in extremely aggressive environments. This includes coastal areas with high salt spray, industrial zones with chemical exposure, or river applications with acidic water. The PVC layer acts as a robust chemical barrier, protecting the underlying metallic coating and dramatically extending the system's lifespan to potentially 120+ years.

ETAG 027 is the "Guideline for European Technical Approval of Falling Rock Protection Kits." It is a comprehensive standard that outlines the testing procedures and performance requirements for systems designed to stop rockfalls. It involves full-scale impact testing to classify a system's Maximum Energy Level (MEL) absorption capacity. Specifying a product that complies with ETAG 027 ensures the rockfall protection netting has been rigorously tested and its performance is verified, providing a high degree of safety assurance.

Absolutely. This is one of the key environmental benefits. Simple rock netting (drapery) allows natural vegetation to grow through it. For active systems or in conjunction with erosion control mats, the mesh can be hydroseeded. The roots of the vegetation then interlock with the soil and the mesh, creating a "green" living composite structure that further enhances slope stability and aesthetic appeal.

A passive system (like a drapery or catch fence) is designed to control or stop rocks after they have detached from the slope. A simple rock netting drapery guides falling debris safely to the toe of the slope. An active system, on the other hand, is tensioned and anchored to the slope to prevent rock detachment in the first place. It applies a stabilizing pressure to the rock face. High-tensile steel grids like TECCO are typically used for active stabilization.

Maintenance is generally low but crucial. It involves periodic inspections (typically annually and after major storm or seismic events) to check for damage to the mesh from rock impacts, assess the condition of anchors and cables, and clear any significant accumulation of debris that could overload the system. Minor repairs can be made by patching damaged mesh sections. For our Gabion Wall systems, inspection for settlement or bulging is also recommended.

Anchor selection is critical and depends on the geotechnical conditions (rock quality, soil type) and the loads imposed by the system. Common types include grouted rock bolts for competent rock, mechanical anchors for moderately fractured rock, and soil nails or helical anchors for soil slopes. A qualified geotechnical engineer must perform a pull-out test on-site to verify the capacity of the chosen anchor type before full-scale rockfall netting installation begins. We can provide guidance on anchor selection based on your project data.