The investigation of the geology and material properties and the durability of Buca green andesites

The green andesite, used widely in İzmir - Buca, has also been extensively used as a building material for the exterior walls of the historical buildings in İzmir. Green andesite; beside its color and pattern properties, offers massive appearance which had caused to attack strong demond in the near past.Firstly in this study, the location of the quarry where the green andesite had been excavated, was determined. Then, the mineralogical, chemical, physical and the mechanical properties of the green andesite samples taken from the old quarry were determined and these values were correlated with the related standards. Ageing tests such as Na2SO4 and MgSO4 salt crystallization, freezing ? thawing and wetting ? drying were conducted on the fresh andesite core samples to assess their durability in different environmental conditions. In addition, the durability of the green andesiteis also evaluated by determining its average pore diameter, saturation coefficient, wet to dry strength ratio, static rock and slake - durability indices.Buca green andesite is defined as thetrachy-andesiteaccording to its mineralogical and chemical compositions andis found to have physical and mechanical properties close and or above the threshold values given by the Turkish standards. The average pore diameter and saturation coefficient index values indicate that Bucagreen andesite is frost-susceptible and has wet-to-dry strength ratio;slake-durability index and the static rock durability index values indicate that Bucagreen andesite is very gooddurable stone.