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Dagmar Havlíčková
Martin Závacký
Lukáš Krmíček


The paper brings the description of the mechanical properties of greywacke sampled in Kobeřice quarry (Lower Carboniferous Culm Basin, Drahany Uplands, Bohemian Massif). Anisotropy of mechanical properties was identified from a series of laboratory tests of oriented samples using the following procedures: (1) indirect tensile testing, (2) uniaxial compressive testing and (3) triaxial compressive testing. Parameters of Mohr-Coulomb and Hoek-Brown failure criteria were determined by the evaluation of the obtained laboratory data. The tested greywacke performed relatively high uniaxial compressive strength, roughly 200 MPa. Better fitting by Mohr-Coulomb criterion was identified than by Hoek-Brown one within the investigated interval of confining stresses (0-15 MPa). In addition, Schmidt hammer test was carried out with a comparison of several correlation relationships to uniaxial compressive strength which was compared with the directly obtained value from laboratory tests.

Keywords: greywacke, uniaxial compressive strength, triaxial compressive strength, splitting tensile strength, failure criterion, Schmidt hammer, correlations


Article Details

Research Paper
Author Biography

Lukáš Krmíček, Brno University of Technology, Faculty of Civil Engineering, AdMaS Centre, Veveří 95, CZ-602 00 Brno, Czech Republic

Institute of Geotechnics - associate professor