The future of civil and mining tunnelling and underground space in Australia

Abstract

Underground construction in Australia has surged over the past decade, in particular projects involving inner city road and rail infrastructure. By 2004, tunnel construction in the nation's capital cities will be proceeding at unprecedented levels. Civil tunnelling and tunnelling associated with metalliferous mining in Australia accounts for an annual tunnelling advance of approximately 625 km for a population of approximately 20 million people. Approximately 4% of this (25 km/a) is civil tunnelling in our capital cities. Because of the large annual tunnelling advance, by world standards, Australia has considerable expertise in tunnelling in a large variety of ground conditions. The development of the infrastructure of our major capital cities will require increased tunnelling in the future. In these cities, as surface ring road systems are reaching their peak capacity, they are being paralleled by underground tunnel systems. In Brisbane, an underground rail system is being proposed to reach suburbs currently not serviced by rail and to service the inner CBD area better. Underground space commercial development is the next area of development that needs assessing by the urban planners and this has application in all of the capital cities in Australia. Sydney and Brisbane are ideally suited to this type of development because of their good ground conditions and it is necessary that planning allows for future underground space developments. Australia should sustain an annual tunnel advance, for civil purposes, of approximately 20 km/a from 2006 onwards. Projected tunnelling in Australia from 2004 to 2007 is summarised in Table 1. Australia is a world leader in underground tunnelling technology and application of tunnelling techniques. City planners have identified the benefits of tunnels in the design of infrastructure for our expanding cities. These benefits include improved amenity for urban dwellers, improved commuter travel times and reduced impact on the city landscape. The quality of air emitted from exhaust stacks on long tunnels remains the greatest community concern in regards to tunnel projects and this needs to be addressed in tunnel design. Underground space commercial development is an untapped use of tunnels in Australia which will advance over the next decade. (A). Reprinted with permission from Elsevier. For the covering abstract see ITRD E124500.