MINAX® 80/4 surface support mesh
A 4 mm high-tensile (≥ 1,770 N/mm²) steel wire mesh for heavy static loads and rockburst conditions. Higher load and displacement capacity than welded mesh according to quasi-static tests by the Western Australian School of Mines (WASM); mechanical installation with MESHA.
What it does
MINAX 80/4 has the same structure as MINAX 80/3 with a thicker wire: for holding the surface beyond fall-of-ground conditions, under rockburst and blast-induced dynamic loading. Based on quasi-static tests by the Western Australian School of Mines (WASM), the manufacturer reports that MINAX meshes woven from 1,770 N/mm² wire carry a much higher load and displacement capacity than welded mesh (5.6 × 100 × 100); the test curves are in the manufacturer's brochure. The product is Geobrugg AG's.
Data
| Property | MINAX 80/4 (manufacturer's product information) |
|---|---|
| Wire | 4 mm, high-tensile steel, at least 1,770 N/mm² |
| Behaviour | High static and dynamic capacity, limited deformation that does not endanger the tunnel opening ("balanced stiffness") |
| Structure and edge | Diamond-mesh chain link; knotted ends, little overlap |
| Connection | G-PLATE six-point plate; T3 clip |
| Installation | By hand or mechanically with MESHA; together with MESHA the manufacturer's standard mesh is 80/4 |
| Coating | Hot-dip galvanized, ULTRACOATING, SUPERCOATING, stainless steel, PET-coated wire |
The manufacturer's overlap comparison: large panels and rolls give fewer joints over the same area and a more flexible bolt pattern; numbers and roll size are written in the quotation with their document.
Where it is chosen
- In deep mines with rockburst risk and in drifts close to blasting.
- In sections where limited deformation under heavy load is required (keeping the drift section).
- In jobs where mechanical installation is planned: MESHA + 80/4 is the manufacturer's standard pair.
For dimensioning mesh, bolts and shotcrete together in underground support, see the decision table on the mining and tunnelling page. The lighter version: MINAX 80/3.
Source: Geobrugg AG, "Specific solutions for the mining industry" brochure (WASM test graph) and MINAX product information.