Effecs of thermal ageing on calcarenite from Livorno coast (Italy)

The “Panchina” stone widely outcrops along the South-western Tus- can coastline, from Italy. It is a highly porous calcarenitic rock charac- terized by grains with medium size, enriched in carbonate fragments of organic origin. Panchina stone is made up of abundant calcite and quartz, subordinate feldspars, and traces of phyllosilicates. The ana- lysed samples are characterized by high porosity, highly variable wa- ter absorption by both capillarity and total immersion at atmospheric pressure. Thanks to the good physical and mechanical properties that characterize the stone, the “Panchina” calcarenite is easy to work and extensively used in the necropolis of the Gulf of Baratti since Etruscan times and, in medieval times, in various public and religious buildings in the city of Pisa. This work focuses on the effects of degradation produced by artificial thermal decay. The exposition of samples at in- creasing values of temperatures (110 °C, 200 °C and 300 °C) brings the samples to an increase in the amount of absorbed water (from 11.79 to 12.21 vol. % at 300 °C) and, therefore, to an increase in total porosity. This can bring to a higher circulation of fluids in the rock that can play a key role in it decay.