This dataset provides friction data from ring-shear tests (RST) on glass beads used in the Helmholtz Laboratory for Tectonic Modelling (HelTec) at the GFZ German Research Centre for Geosciences in Potsdam as an analogue for “weak” brittle layers in the crust or lithosphere (Ritter et al., 2016; Santimano et al., 2015; Contardo et al., 2011; Reiter et al., 2011; Hoth et al., 2007, 2006; Kenkmann et al., 2007; Deng et al., 2018) or in stick-slip experiments (Rudolf et al., 2019). The glass beads with a diameter of 300-400 µm have been characterized by means of internal friction coefficients µ and cohesions C as a remote service by the Helmholtz Laboratory for Tectonic Modelling (HelTec) at the GFZ German Research Centre for Geosciences in Potsdam.
According to our analysis the material shows a Mohr-Coulomb behaviour characterized by a linear failure envelope. Peak, dynamic and reactivation friction coefficients of the glass beads are µP = 0.58, µD = 0.43 and µR = 0.49, respectively. Cohesion ranges between 8 and 81 Pa. A rate-weakening of ~7 % per ten-fold change in shear velocity v is evident.