%0 Journal Article
%T Monitoring of travertine changes resulting from thermal load
%A Zuzana Kompan¨Şkov¨˘
%A Tatiana Durmekov¨˘
%A J¨˘n VlŁżko
%A Martin BrŁżek
%J Acta Geologica Slovaca
%D 2011
%I Comenius University in Bratislava
%X Travertines, despite of their unique noble appearance change their properties when affected by ageing like any other building and decorative stone. Some of the most noticeable changes are influenced by temperature fluctuations. From this point of view, the main purpose of presented research was to determine the influence of multiple temperature cycles for travertine from Spi sk¨¦ Podhradie and Ludrov¨˘ in temperature range of 25ˇăC to 60ˇăC corresponding to summer period temperature regimes. The weakening of the rock material by heating was determined by non-destructive techniques before and after thermal load. By ultrasound apparatus was observed by means of ultrasonic velocities change, when higher values of ultrasonic velocities were determined parallel to the bedding while the perpendicular direction had slower velocities. The change of colour was specified by spectrophotometer and no distinct visual colour change was determined with increasing temperature. By non-contact profilometer surface roughness data of samples profiles primarily indicate a decrease of roughness during heating. The coefficient of linear thermal expansion acquired by thermodilatometer varied from 4.6.10-3 to 7.8.10-3 mm.m-1.ˇăC-1 for travertine from Spi sk¨¦ Podhradie and 5.3.10-3 to 7.3.10-3 mm.m-1.ˇăC-1 for travertine from Ludrov¨˘. This parameter characterizes the materials response to heating or cooling. The techniques mentioned above are non-destructive and some of them are innovative in laboratory testing.
%K travertine
%K thermal load
%K linear thermal expansion
%K ultrasound velocity
%K colour change
%K surface roughness
%U http://www.geopaleo.fns.uniba.sk/ageos/archive/2011_01/kompanikova_et_al_2011.pdf