GeoMod2008 materials benchmark: The axial test dataset

This dataset provides compaction data from axial testing on natural and artificial granular materials used for experimental simulation by the analogue geodynamic modelling community (21 sands and glass beads). The material samples have been collected community-wide and analysed at GFZ Potsdam in the framework of the GeoMod2008 conference benchmark initiative. The context of data collection, details of the material samples and measuring techniques as well as interpretation and discussion of results can be found in Klinkmüller et al. (2016) to which this dataset is supplement material.

The data presented here are derived by uniaxial, confined compression testing using the Axial Tester at GFZ Potsdam’s analogue laboratory for tectonic modelling . Each sample has been carefully prepared by the same person and measured consistently following the same protocol. Preparation included sieving at 250 ml/min from 30 cm height into the container (jar). Up to 2000 kPa of uniaxial compression has been applied in 50 cycles. Laboratory conditions were air conditioned during all the measurements (Temperature: 23°C, Humidity: 45%).The resulting stress curve data are presented at 20 Hz frequency and the Unit of N. From the stress curves the compaction data have been derived. These correspond to the normalized sample height (normalized to the initial height) of the sample at the beginning of each cycle and are characterized by an exponential decrease over the 50 cycles. From that the following compaction parameters are derived: total compaction (shortening after 50 cycles Ct=eps50), the compaction during the first cycle (eps1) as well as the compaction index (Ci = eps1/eps50). Compaction data are finally visualized in the compactionDataPlot file.Each material sample has a relation to three files: stress curve data (txt format, 50 files per sample), compaction data (in xls and txt format), compaction plot (pdf format), examples of which are shown below. An overview of all files of the data set is given in the table CompactionDataOverview.xls.