Use of ERT in a Geotechnical Centrifuge

Friederike K Günzel, Colin J Fyfe, Michael C R Davies

Division of Civil Engineering, University of Dundee, Dundee DD1 4HN, Scotland, UK f.k.gunzel@dundee.ac.uk

ABSTRACT

This paper describes a miniaturised electrical resistivity tomography (ERT) system, used to monitor contaminant plume development in a porous material at increased gravity in a geotechnical centrifuge. Data processing is necessary to eliminate the influence of the sample container (strongbox, which is relatively small compared to the length of the electrode array. The data processing technique was developed using high and low resistivity anomalies. Increased gravity tests were carried out at 5g (sand sample) and 10g (silt sample). For these tests dyed brine was used as contaminant to allow simultaneous visual observations. The ERT data show that the NaCl solution spreads further that the dye, which appears to be filtered by the sample.

Keywords ERT, groundwater, contamination plume, geotechnical centrifuge