The Department of Civil Engineering received funding from the National Research Foundation (NRF) and the University to purchase a geotechnical centrifuge in 2012. A geotechnical centrifuge is used to subject small scale models of geotechnical problems to high accelerations. Because the stress-strain behaviour of soil is highly non-linear, high accelerations are necessary to impose full-scale stresses on models tested to ensure that the soil in the models strain realistically. Our geotechnical centrifuge is capable of accelerating models weighing up to one ton to 150 times earth’s gravity (150G). The centrifuge is a fourth generation C67 geotechnical centrifuge manufactured by Actidyn in France.
The centrifuge laboratory is located in the basement of the Heavy Machine Laboratory B on the University’s main campus in Hatfield, Pretoria. In addition to state of the art research facilities, the laboratory is equipped with projection facilities to accommodate large groups. The centrifuge is equipped with the German HBM data acquisition system and the Digidaq system developed at the University of Western Australia. It also includes two solid state on-board computers to control various types of instrumentation and cameras. In addition to standard measurement equipment like a range of digital cameras, web cams, LVDTs, potentiometers, piezometers and tensiometers, other facilities available include two stepper motor controlled multi-purpose jacks, a laser surface scanner and pressure sensor mats by Tekscan ™. We also make use of fibre optic strain measurement using Bragg gratings on the centrifuge.
The primary purpose of the centrifuge is for research of geotechnical, geological and mining related problems by means of testing physical models. It is also available for commercial testing. Research projects currently underway include:
- Modelling flow failures of tailings dam slopes
- A range of soil-structure interaction problems (latest: modelling piled foundations in expansive clay)
- Physical modelling of expansive soil profiles
- The physical modelling of dolomitic sinkholes
- Physical modelling of cave mining incorporating acoustic detection
- Geosynthetic reinforcement of clay liners
- Geosynthetic reinforcement of soil mattresses
More information about the centrifuge laboratory can be found here.
A list of current research activities involving centrifuge modelling can can be accessed here.
Please contact Prof SW Jacobsz for further information ([email protected]).