At ATC Williams we have a strategic focus on research and innovation that addresses the challenges of our main stream business tailings and water management for mining industries. This has resulted in great outcomes for our mining clients by providing innovative and competitive solutions. Over the past three decades we have initiated and carried out a number of research projects in collaboration with universities and research institutes.
Examples of some of our recent initiatives and research studies are provided below.
Embankment dams are often required in construction of tailings storage facilities, and rockfill materials have been widely used in construction of this type of dams around the world. Rockfill is a coarse grained material with essentially rock particles ranging from gravels (+2mm) to cobbles (+60mm) and boulders (+200mm) with the maximum size usually limited to 1m. Currently there is no formally accepted model for the analysis of the mechanical behaviour of rockfill due to complex interactions of particles not being fully understood. This research could potentially result in significant cost savings by allowing designers to adopt less conservative geometries in design of rockfill embankment dams, waste rock dumps, and other rockfill structures.
The shear testing of rockfill is very expensive and time consuming, and requires large apparatuses which are scarce. As a result, determination of rockfill strength for design purposes has been mainly based on empirical relationships and correlations developed from the results of large scale triaxial tests which were carried out prior to 1970.
Dr Behrooz Ghahreman-Nejad, a Principal Geotechnical/Dams Engineer at ATC Williams, initiated a research project in 2014 at the Department of Infrastructure Engineering, University of Melbourne, on mechanical behaviour of rockfill materials. Behrooz is an Honorary Senior Fellow at Melbourne University and in his role has engaged postgraduate students to carry out experimental research on this topic.
To date, 4 master’s degree students have completed their theses in this area. It is intended to further progress the understanding of the mechanical behaviour of rockfill and produce experimental data for development of theoretical and numerical models employing a discrete element method (DEM). Negotiations are currently underway to secure research funds for a PhD student to continue on the theoretical/numerical aspects of this research. It is proposed to numerically carry out triaxial tests in order to study the stress-strain response and strength characteristics of rockfill by employing the commercial software PFC 3D (Particle Flow Code in 3 dimensions) which is a DEM code. The effects of different parameters which are known to influence the strength of rockfill, such as relative density, gradation, particle strength and shape, will also be investigated.
Other Research Proposals
Other Research proposals that are currently being developed are as follows:-
- Improving tailings consolidation by employing innovative techniques such as electro-osmosis, wick drains, etc.
- Large strain consolidation modelling of tailings
- Seismic liquefaction
- Back analysis of slope failures in mine spoil
- Seismic/dynamic deformation analysis of embankment dams
By working collaboratively with universities we believe we could solve some of the challenges facing the mining industry today in the fields of tailings and water management.
Dr Behrooz Ghahreman-Nejad with ATC Williams Laboratory Staff John Walker and Luke Renkin.
For further information please contact:
Behrooz Ghahreman-Nejad on 0423151019 or via email at firstname.lastname@example.org or
Charles Vuillier on 0435087562 or via email at email@example.com