Engineering Geological Properties of Building Stones from the North-Eastern Part of the Vienna Basin in the Western Carpathians

This research focuses on assessing the most important physical and mechanical properties of rocks that were quarried from the north-eastern part of the Vienna Basin in the Western Carpathians. Carbonate conglomerates and sandstones of Neogene sedimentary strata were assessed. The engineering geological rock properties were evaluated with support by sedimentological, petrological, as well as macro and micro-analyses. The sites, Chtelnica-Trianova and Chtelnica-Male Skalky, Slovakia had been chosen long ago as an appropriate location for collecting material for monuments and restoration work. Samples for the assessment of rock properties were taken from either abandoned or operating quarries, as well as artificial rock cuts. The testing specimens, in the form of cubes and cylinders, were prepared from extracted monoliths, and the drilled cores were taken from a depth up to 1 m within the rock mass. Thin sections were made from just one drill core taken from each investigated site. The rock quality and durability were assessed by laboratory testing for the physical and mechanical properties of the rock samples. The tests were oriented to specific and bulk density, porosity, water absorption capacity, uniaxial compressive strength (UCS) for dry and water-saturated rock samples and samples following repeated freeze-thaw cycles, the coefficient of softening, and the coefficient of freezing. All of the investigated rock samples showed different porosities and absorption capacities. They also varied in UCS values. The rocks mostly belong to the weak rock category (UCS below 50 MPa). Based on the results of this research, uniaxial strength properties, coefficient of softening and freezing, porosity, and water absorption capacity are considered the most relevant criteria for rock quality and durability assessment. Mutual relations in selected properties were compared and analysed.