Fire resistance of the Mt. Epomeo Green Tuff, a widely-used building stone on Ischia Island (Italy)

Volcanica

Fabian Wadsworth¹  Luke Griffiths²  Salvatore Martino³  Matteo Fiorucci³  Gian Marco Marmoni³  H. Albert Gilg⁴  Michael Heap⁵  Patrick Baud⁶  Alexandra Kushnir⁶  Thierry Reuschlé⁶ 

[1] Durham University;Norwegian Geotechnical Institute: Oslo;Sapienza University of Rome;Technische Universität München;University of Strasbourg;Université de Strasbourg;

关键词: Fire;    Tuff;    Strength;    Acoustic emissions;    Thermogravimetry;    Porosity;   

DOI  :  10.30909/vol.01.01.3348

来源: DOAJ

【 摘 要 】

The use of Mt. Epomeo Green Tuff (MEGT) as a building stone is widespread on Ischia Island (Italy). We assess here the fire resistance of MEGT by thermally stressing samples to temperatures up to 1000 °C. Porosity and uniaxial compressive strength increase and decrease from 44% and 4.5 MPa at ambient temperature to 48% and 1.5 MPa following exposure to 1000 °C, respectively. Complementary thermogravimetric and X-ray powder diffraction analyses, experiments that monitor acoustic emissions during heating/cooling, and microstructural observations highlight that these changes are the result of thermal microcracks, formed due to the breakdown of zeolites and clays (MEGT contains 35 wt.% analcime, 15 wt.% smectite, and 3 wt.% illite) at high temperature. Although the stability of structures built from MEGT will be jeopardised at high temperature, a very low thermal diffusivity requires that fires must burn for many hours to compromise the strength of a typical dimension stone: tuffs are tough in the event of fire.

【 授权许可】

Unknown