Brček M., Vlčko J., Kubičár Ľ., Boháč V. & Adamcová R., 2009: The moisture – a negative deterioration factor of rock mass. Acta Geologica Slovaca, 1, 1, 1–8. (in Slovak with English summary)

Vlhkosť – negatívny faktor deteriorácie horninového masívu

The moisture – a negative deterioration factor of rock mass

Martin Brček¹, Ján Vlčko¹, Ľudovít Kubičár², Vlastimil Boháč² & Renáta Adamcová¹

¹Katedra inžinierskej geológie, Prírodovedecká fakulta, Univerzita Komenského v Bratislave, Mlynská dolina G, 842 15 Bratislava; e-mail: brcek@fns.uniba.sk
²Fyzikálny ústav, Slovenská akadémia vied, Dúbravská cesta 9, 845 11 Bratislava

Abstract

The rock mass deterioration is caused by exogenous factors from which the main role play the temperature and moisture content. A monitoring system of the rock moisture content based on the transient Hot-ball method of measuring of the thermal conductivity of materials was installed on the Perún's rock at the Spiš Castle. So called, hot ball method was used for the estimation of the water content in various depths inside the rock mass in order to assess its effect on the temperature penetration depth beneath the surface, which might control the volumetric change (dilation) of the rock cliff and its stability. The preliminary results showed relation between q/T_m index and the precipitation registered by the nearby meteorological station. This dependence was manifested in the near subsurface parts of the rock face while the deeper sensors were not influenced. This suggests that the surface parts of the travertine rock body are more prone to the temperature dilation effects and therefore the thermal flux through the upper 40 cm of rock is faster than through the deeper parts.

Key words: rock mass, water content, q/T_m index, thermal conductivity, penetration depth, Spiš Castle

Manuscript received: 2009-06-12

Revised version accepted: 2009-07-29