Mikula, P, Bruce, S, Sasi, G, Dissanayake, T, Power, W & Hafeez, F 2026, 'In situ quasi-static capacity testing and failure behaviour of weldmesh and chainlink mesh under field boundary conditions at a hard rock mine in Western Australia', in D Cumming-Potvin & J Wesseloo (eds), Ground Support 2026: Proceedings of the 11th International Conference on Ground Support in Mining, Australian Centre for Geomechanics, Perth, pp. 1-19, https://doi.org/10.36487/ACG_repo/2625_18 (https://papers.acg.uwa.edu.au/p/2625_18_Mikula/) Abstract: In situ quasi-static testing was conducted at an underground mine to measure performance of weldmesh and chainlink mesh installed in typical configurations used in Australian hard rock mining. The motive for the testing was to compare mesh (or screen) products for use in seismic environments, providing engineers with mesh performance data relevant to actual field boundary conditions. A series of 22 in situ tests were conducted to determine the capacity and failure behaviour of the meshes. Laboratory testing indicates a wide range of energy capacities depending on the test method and configuration, making it difficult to confidently appraise a mesh based on laboratory data alone. The field test used a hydraulic ram to tug the mesh away from the rock surface. Test configurations included baseline mesh sheets or rolls bolted on a 1.1 × 1.4 m pattern, with variations comprising deliberately cut wires, loading at centre of sheet or at mesh overlap positions, and with fibrecrete overspray of boundaries to emulate laboratory locked-perimeter test configurations. Results showed stiffness, displacement capacity, reaction pressure and rupture vulnerability were sensitive to mesh type, test configuration and boundary conditions. Weldmesh energy capacity in most configurations was higher than for chainlink mesh to the limit of the test equipment. Beyond about 0.6 m displacement, chainlink mesh energy capacity in some configurations equalled that of weldmesh, and with further displacement it likely would be superior to weldmesh, but that was not able to be assessed in these tests. Chainlink mesh was observed to be substantially compromised by unravelling if a cut wire was present. Only one test configuration, with fibrecrete spray to lock the perimeters of the test panel, came close to the high load and energy capacities at small displacements reported in some locked-perimeter laboratory tests. Overall the testing provides guidance to assist engineers evaluate likely performance of mesh configurations in their mines. Keywords: weldmesh, chainlink mesh, in situ testing, energy capacity, surface support, seismicity, strainburst