Engineering geological properties of Leitha Limestone from historical quarries in Burgenland and Styria, Austria

This research has focused predominantly on assessing the most important physical and mechanical properties of Leitha Limestone rock samples and of a separate oolitic limestone sample, in conjunction with sedimentological and microfacies analyses. The microfacies characteristics of these samples, together with their other technical properties, help to explain why the Leitha Limestone is an important material for monuments and for restoration work. amples for laboratory tests were collected from 12 sites located within alpine Neogene basins. Samples for the assessment of rock properties were taken from abandoned quarries in the Kaisersteinbruch–Bruckneudorf military area, from abandoned and active quarries at St. Margarethen, and from the Aflenz underground quarry. To broaden the scope of the investigations previous research results from quarries at St. Margarethen, Mannersdorf, Wolfsthal, and Hundsheim were also included. Thin sections were made from one of the drill cores from each quarry. The microfacies analysis of the Leitha Limestone samples indicated a spectrum from encrusting coralline algae boundstones to coralline algae grainstones and rudstones, and also included variable quantities of other bioclasts and siliciclasts. The detailed results revealed considerable differences between the various samples, which are considered to be from a shallow marine, intertidal to subtidal paleoenvironment with variable hydrodynamic conditions. ck quality and durability were assessed through laboratory testing of physical and mechanical properties, including measurements of real and apparent density, porosity, water absorption capacity, uniaxial compressive strength (UCS) for both dry and water-saturated rock samples and for samples following repeated freeze–thaw cycles, the coefficient of softening and the coefficient of freezing. All investigated rock samples had different porosities and absorption capacities. They also differed in their UCS values, which were very variable but mostly belonged to the weak rock category (UCS below 50 MPa). Five of the tested rock samples had higher UCS values and were consequently ranked in the firm rock category. The microfacies investigation proved to be a valuable tool for interpreting the measured engineering geological properties, in particular the porosity and rock strength.