ROCKFALL

Key Researchers, Anna Giacomini, Olivier Buzzi, Klaus Thoeni, Stephen Fityus

PROBLEM DESCRIPTION

Rockfall presents a significant risk to users and infrastructure in coastal areas, mountainous areas and along transport corridors of Australia, including in New South Wales. The Bulli pass, south of Wollongong, made the headlines in 2015 when a boulder hit a car with two persons on board (https://www.smh.com.au/national/nsw/the-car-just-exploded-couples-bulli-pass-rockfall-ordeal-20150211-13bfjc.html). Such risk needs to be managed by the relevant authorities. Assessing the risk is a multifaceted process which involves identifying and characterising the potentially unstable blocks, evaluating their possible trajectory following detachment and assessing whether these blocks are likely to fragment upon impact in order to produce a risk zonation. It is then often required to design protection systems to mitigate the rockfall risk, which is achieved by quantifying the impact energy, bouncing heights and run out distances. There exist significant knowledge gaps in all the steps described above, partly because the Australian context is different from high mountainous areas of Europe, Northern America and Japan where most of the rockfall knowledge emanates from; partly because some of the phenomena are very complex and not well studied (e.g. fragmentation upon impact) and partly because of the incessant evolution of technology and systems. Our research team is conducting world class research on all the aforementioned aspects of rockfall.

SCIENTIFIC AND ENGINEERING APPROACHES

  • Geostructural characterisation of rock faces using remote sensing and 3D reconstruction to characterise distribution, volume and location of potential unstable blocks
  • In situ tracking of block trajectory and computer modelling of trajectory using in-house code.
  • Experimental testing of rock blocks fragmentation upon impact with 3D tracking of fragments and estimation of fragmentation energy.
  • Testing of full protection systems or individual components of protection systems.
  • DEM and FEM modelling of full protection structures (drapery systems, low energy barriers) including characterisation of effect of block size on the response of the system.

APPLICATIONS

  • Estimation of rockfall impact energy accounting for fragmentation.
  • Design and optimisation of rockfall protection systems
  • Qualitative and Quantitative rockfall risk assessment in mining and civil environments

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