More and more underground mines are experiencing rockburst, which is a stress-induced violent ejection of rock that is normally encountered in deep mines. There are different approaches to determine the energy from rockburst, which is caused by excess stress concentrations in the rock mass. A major engineering challenge for mines experiencing this significant seismicity is to design the dynamic performance of their support systems. Therefore, a retaining system using dynamic rockbolts in combination with high-tensile steel wire mesh was tested to ascertain the behaviour and quantify the suitability of the system. A special large scale test facility was constructed for the purpose, which allowed verification of the percentage of energy transmitted by the rockbolts and wire mesh, based on the input energy. Numerous tests were carried out providing first findings on the load distribution within the support system.

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The stability of newly cut or natural slopes is an important issue of geotechnical engineering. Regardless of the scale of the project, the design and the execution have to assure maintenance-free and, more importantly, safe utilisation of the slope. Nowadays, a geotechnical engineer can choose from a number of different, available slope stabilisation methods. Nevertheless, one of the most frequently chosen methods is soil nailing in combination with flexible facing. In this configuration, the soil nailing is designed to stabilise deep-seated instabilities, while localised instabilities have to be stabilised by the flexible facing, typically represented by high-tensile steel wire mesh. In order to assure proper slope stabilisation, the soil nails and the flexible facing have to act as one integrated system. Such a system has been tested lately in large scale within this R&D project supported by the Swiss Commission for Technology and Innovation (CTI). The large-scale setup, widely described in Cała et al. (2013), consisted of an inclinable large box (12 × 10 × 1.2 m), soil material, soil nails, high-tensile steel wire mesh, steel plates (linking nail heads and mesh), connection clips (linking two sheets of mesh), and boundary ropes. The entire setup was lifted up on one side to imitate the inclination of the slope. While lifting the box up, several measurements were taken, e.g. tension forces and bending moments in the nails or deformation of the mesh. In total, 31 large-scale tests were conducted, at first to check the testing setup and later to test the interactions of the nails and high-tensile steel mesh, which were put together in different arrangement and configurations. The most important testing variables were soil material, nail pattern, type of steel wire mesh and connection plate. The main aim of this paper is to present the analysis of the performance of three meshes composed of 2, 3 and 4 mm diameter wire, tested in comparable conditions (the same soil conditions, nail pattern and connection plate). The purpose of this analysis was to show the distinction in bearing capacity and range of deformation of meshes produced from the same steel but of different wire diameter. This analysis was also used for the purpose of validation of already existing dimensioning concept based on small scaled laboratory tests. https://papers.acg.uwa.edu.au/p/1604_49_Bucher/ New results of large-scale testing of high-tensile steel meshes and soil nails for slope stabilisation R Bucher et al. and validation of modelling software 710 APSSIM 2016,

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Increasing stresses and seismicity with the resulting rockburst hazard is a threat for deep hard rock underground mines. High-tensile chain-link mesh has a proven capability of absorbing rock falls in surface applications and was adapted for the use in underground workings. Due to the high-tensile wire strength and ability of the chain-link mesh to deform, this ground support system can be used in high stress environments.A mechanised 'roll mesh handler' for the application of the high-tensile chain-link mesh was developed and successfully tested in Australia and Switzerland for use as support in underground tunnels. The application of the mesh and the installation of split-sets or rock bolts occur simultaneously. The mesh handler technology increases productivity due to reduced support cycle times (trials suggest a 30-50% quicker installation time over current sheet mesh methods); improves quality (high-tensile mesh can be tensioned and contours more closely to the rock surface) and improves safety (due to reduced manual handling without exposure of personnel in un-supported ground due to fully mechanised handling during the installation process).Ground support in high stress mining with high-tensile chain-link mesh with high static and dynamic load capacity R. Bucher et al.