The earth in the architecture of the historical centre of Lamezia Terme (Italy): Characterization for restoration

摘要

In Calabria (Italy) original examples of earth buildings called "casedde" are present distinguished from the houses realized in stone or bricks that are indicated with the term "casini" or "turri". The historical centres of Sambiase and Nicastro, villages which belong to the municipality of Lamezia Terme, in the Tyrrhenian side of Catanzaro province, are an example of urban centres in which there are buildings of 4-5 floors completely or partially realized in earth bricks (adobe) connected with a mortar made of clay and lime. In the present study the mineralogical, physical and mechanical characterization of adobe samples coming from seven different buildings in a poor state of conservation has been carried out together with an analysis of the "Local Earth" for comparison. The analyses showed the absence of any mixing intervention in the earth except for the possible addition of straw. It was also possible to discover which optimum amount of clay is needed in order to have the best mechanical characteristics for that kind of earth. Moreover it was possible to emphasize that the new bricks, realized with the earth taken where the local masons indicated the presence of material suitable for the realisation of earth bricks, exhibit a mechanical behaviour similar to that of the old bricks with the best mechanical characteristics. Such earth can surely be utilised in consolidation interventions where substitutions and partial reconstructions of bricks are needed.