Dear clients,

The second part of the 2016 year will be rich in events with the release of two of our 3-dimensional software: 3DEC v5.2 is already available and FLAC3D v6.0 will be released within the following months. All our 3DEC and FLAC3D users can benefit from lower prices on the pre-purchase until their official release. PFC Suite users are also invited to contact their local agent to renew their Annual Maintenance Program and thus to benefit of the next upgrades and major releases.

All the Itasca team is available to answer your enquiries and assist you in your decision.

The European Itasca team


Itasca Consultants AB (Sweden) has conducted a mine-scale stress calibration for the LKAB Malmberget Mine. The mine comprises 20 orebodies of varying size, shape and orientation, over an area of 8 km2 (Figure 1) A detailed, mine-scale, three-dimensional model was setup using FLAC3D (Figure 2). The model included the currently known mineralizations, some reaching down to mining level 1600 m. The model also incorporated extensive biotite zones near two of the orebodies. A unit stress tensor approach was used for model stress calibration, in which unit stresses of each tensor component was applied to the model, and the stress response calculated. These response tensors were combined (using superposition for linear-elastic analysis) and the results fitted to stress measurement data. This approach provided an unbiased methodology for stress calibration, which accounts for influences from mining and variations in material properties. The end result of this work was a calibrated three-dimensional model including all actively mined orebodies at the mine. The results from this model provided knowledge about stress distribution effects globally and locally in the mine, as well as input to local model of drifts, shafts, and other critical underground excavations. The model is also used for the planning and design work for potential continued mining at depth in the Malmberget mine. This work was presented at the 7th International Symposium on In-Situ Rock Stress in Tampere, Finland (May 10-12, 2016).


Fig. 1 - Orebodies included in the model

Fig. 2 - Model geometry and size, including orebodies



Itasca Consultants S.A.S (France) has evaluated the feasibility of using the distinct element modeling to study the flow and segregation of frictional particles without cohesion. We have simulated an experimental test corresponding to the charge/discharge of a scale model batch hopper then analyzed the segregation observed in the hopper after its charge and its discharge and finally compared against experiments: geometry and parameters were specified by ArcelorMittal.
A new rolling resistance contact law was developed and applied on spherical particles instead of using the real grain shapes. This model allows the repose angle of the real material to be simulated. The end results of this work were: 1. The observation of segregation mechanisms during the charge of the hopper: smaller particles tend to concentrate in the inner cylinder, while bigger particles concentrate nearby the hopper walls (Fig. 1). 2. The flow during the discharge can be characterized as a funnel flow (Fig. 2).

The time evolution of the harmonic diameter during the discharge process can be measured and well explained by both the segregation observed at the end of the charging phase and the funnel flow. Discharge time in the simulation is comparable with the experiments (total discharge in 9.3s in the simulation compared to 10.1 s experimentally). The numerical results show a quadratic evolution of the harmonic diameter, whereas it seems more linear in the experiments (Fig. 3): grain breakage during impacts and/or particle attrition occur during the experiment (not modelled).


Fig. 1 - Visualization of the segregation in the final steady state (427,878 grains)



Fig. 2 - Contour on initial z-pos – t = 3s (initial Z-pos - t=0s at the bottom left)


Fig. 3 - Harmonic diameter vs Discharge time



Current Updates:









Training & Seminars

Itasca will host introductory training courses in Europe:

FLAC3D Training course Ecully, France Fall 2016 Itasca France

Please visit for full details.

For users who envisage the need for substantial amounts of assistance, consulting support or customized training course are available.
Accordingly, users are encouraged to submit sample problems prior to the training session for our review and preparation. These problems would then be used as practical applications of the code during the training sessions.


Itasca will be attending the following conferences:

Geotechnica 2016 6-7 July 2016 London, UK
JNGG 2016 6-8 July 2016 Nancy, France
3rd International Symposium on Mine Safety Science and Engineering 13-19 August 2016 Montreal, Canada
EUROCK 2016 29-31 August 2016 Cappadoce, Turkey
8th International Symposium on Ground Support in Mining and Underground Construction 12-14 September 2016 Luleå, Sweden
Soil Mechanics and Geotechnical Engineering 16th National Congress 13-15 October 2016 Erzurum, Turkey

Recent Publications

Vatcher, J., S. D. McKinnon and J. Sjöberg (2016) – "Developing 3-D mine-scale geomechanical models in complex geological environments, as applied to the Kiirunavaara Mine", in Engineering Geology, Vol 203, pp. 140–150 (

J. J. Oetomo, E. Vincens, F. Dedecker, J-C. Morel (2016) - "Modeling the 2D behavior of drystone retaining walls by a fully discrete element method", in Int. Journal for Numerical and Analytical Methods in Geomechanics, to publish

Sjöberg, J., A. Bolin, A. Sánchez Juncal, T. Wettainen, D. Mas Ivars and F. Perman (2015) – "Input to ore pass design – a numerical modelling study", in Proceedings of International Seminar on Design Methods in Underground Mining, Potvin, Y,. (eds.), pp. 571–584. Perth: Australian Centre for Geomechanics (17–19 Nov, 2015, Perth, Australia)

Tran M. H., Sulem J., Subrin D. and Billaux D. (2015) - "Anisotropic Time-Dependent Modeling of Tunnel Excavation in Squeezing Ground", in Rock Mechanics and Rock Engineering, DOI: 10.1007/s00603-015-0717-y

Ghazal R., Mas Ivars D., Johansson F. and Batres-Estrada R. (2015) - "Back analysis of in situ stress at shallow depth using discontinuum numerical modeling - a case study at the Odenplan station in Stockholm". Proceedings of Eurock 2015, Salzburg, Austria (October 2015)

Moreno J., Senis M. and Olalla C. (2015) "Aspectos necesarios a introducir en la modelización numérica 3D de las presas de escollera con pantalla de hormigón para reproducir correctamente las tensiones en el elemento de impermeabilización ", In X Jornadas Españolas de Presas, Spancold, Sevilla (18-20 February 2015)

Graf F., te Kamp L., Auer M., Acharya M. and W. Wu (2015) – “Soil aggregate stability in eco-engineering: comparison of field and laboratory data with an outlook on a new modelling approach”, in Recent Advances in Modeling Land-slides and Debris Flows. Springer Series Geomechanics and Geoengineering, pp. 29-47.

Wu W., Switala BM., Acharya M., Tamagnini R., Auer M., Graf F., te Kamp L. and W. Xiang (2015) – “Effect of vegetation on stability of soil slopes: numerical aspects”, in Recent Advances in Modeling Landslides and Debris Flows. Springer Series Geomechanics and Geoengineering, pp. 163-177.

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Itasca Consultants S.A.S
64 Chemin des mouilles
FR-69134 Ecully Cedex

© 2016 Itasca Consultants S.A.S.