Mechanical characterizatiion of adobe bricks: ancient constructive elements for an eco-friendly buliding renovation.

Earth buildings have a strong connection with the environment, due to the local materials used and the specific techniques used. The current presence of ancient buildings models that involves raw earth, mostly in rural areas, is the result of countless trials methodologies employed in the local landscape that have allowed the creation of resisting constructions in the time. Along the Herculia Way, an ancient road dating back to the roman epoch, that connects the north to the south of the Basilicata Region (Southern Italy), there are many buildings realized with earth, particularly clay, wood and other natural materials. A requalification and maintenance of these buildings and infrastructures could significantly contribute to the exploitation of rural tourism, aiming to support local economies of these areas that are mainly devoted to agricultural production. In these areas, an additional resource to be exploited for the local development is represented by the vernacular unused buildings, that could be restructured using the same natural materials, so respecting the local culture and landscape. In order to identify the construction methods of these old buildings and the mechanical behaviour of their constructive materials, some laboratory tests on specimens taken from old adobe houses have been conducted in the laboratory of material testing of the SAFE School of the University of Basilicata. Compression tests were also conducted on two new specimens realized with a mix of clay and straw as well, in order to verify the differences between old and new adobe bricks. The new specimens were different between them for the disposition of the straw, respectively random and right-angled layers to the compression load. The first results have shown that the compression strength is higher when the fibers are disposed in a regular way.