Curing of fiber-reinforced thermoset polymer composites requires an elevated temperature to accelerate the crosslinking reaction and also hydrostatic pressure to consolidate the part and suppress the formation of voids. These processing conditions can be provided by autoclaves of appropriate size, but these are expensive and sometimes difficult to schedule. Ultrasonic debulking followed by oven cure is an attractive alternative to autoclave cure. In this technique a movable "horn" driven at ultrasonic frequency is applied to the surface of the uncured part. This generates pressure and at the same time produces heating by viscoelastic dissipation. The part can be debulked to net shape and staged through the action of the ultrasound. There are a large enough number of experimental parameters in ultrasonic debulking and staging to make purely empirical process optimization difficult, and this paper outlines numerical simulation methods useful in understanding and developing the process.

Mining in Western Australia during the next two decades or so will be approaching depths in which the induced stress regimes will approach the strength of the rock masses surrounding excavations. In such conditions, failure may occur violently due to the energy stored within the rock masses. Furthermore, in those highly stressed regions of a rock mass, sudden slip on major structures in the vicinity of the excavations are more likely to occur with an associated release of energy in the form of pressure and shear waves that excite the rock near the boundaries of excavations. In order to be prepared for such scenarios, and to ensure safe and economical excavations in the future, the Western Australian School of Mines (WASM) and a number of sponsoring companies have conceptualised and undertaken a number of research projects in ground support technology. The projects range from static and dynamic laboratory testing of support and reinforcement elements to in situ field testing and assessments of ground support corrosivity. The backgrounds for each of the stabilisation research projects at WASM have been summarised together with details of the methodology, current status, practical applications and future work.

Concerns regarding the uncertainty of stope dilution at MMG Limited's Dugald River Underground Mine led to a trial stoping program to acquire full-scale comprehensive geotechnical information and to test the validity of the proposed geotechnical and mining parameters. As part of the trial, a geotechnical instrumentation program was designed to improve the understanding of the rock mass response to the mining of the trial stopes. This included an array of instruments installed from dedicated hanging wall drives, hanging walls that included 66 multipoint borehole extensometers (MPBX), 23 time domain reflectometers, 24 geophones, six accelerometers and 15 observation holes. Trial mining consisted of 19 sublevel open stopes with cemented rockfill (CRF) that extracted 335 kt of ore, with a panel height of 130 m and strike of 100 m. All stopes were monitored with a minimum of two MPBXs at the open span with a MPBX average density in the panel hanging wall of 180 m 2. The MPBXs were 19 m in length and consisted of six nodes. Instrument displacement information was recorded every 30 minutes by dataloggers to a resolution of 0.12 mm. This provided a high quality, detailed and extensive rock mass response to stope extraction. The displacements were interpreted as hanging wall relaxation and shear on structure from specific stope firing and expansion of the mining front. Rock mass creep was also recorded in the hanging wall. The mechanism of displacement consisted mainly of strike-slip movement on high angle bedding and faults that are orientated sub-parallel to the dip of the orebody. Overall hanging wall behaviour was assessed by investigating the near (stope hanging wall boundary to 6 m) and far (>6 m from stope boundary) displacements as the sequence progressed. The primary rock mass response stage was the extraction of the crown pillar. The secondary responses were associated with the cable bolt arrays mitigating some of the deformation of the hanging walls with more movement mid-span compared to the cable bolt horizon. Finally, the displacement results post-filling showed the backfill mass was being slightly compacted by ground movement.

The Western Australian School of Mines has designed, commissioned and extensively used testing facilities capable of subjecting panels of steel wire mesh to static and dynamic loadings. Since commissioning, a large number of tests have been performed on mesh with different wires diameters and apertures. The forcedisplacement responses of the mesh have been measured and then characterised by various performance indicators such as rupture strength, displacement to rupture and energy absorption. The database of test results has been summarised in the form of charts that may be used to easily compare the performance of different mesh configurations and to assist with design of appropriate ground support for static and dynamic loading applications.

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