Degradation diagnosis on Gravina Calcarenite: Classification and damage indexes on the Sassi di Matera site (Southern Italy)

In Matera, the 2019 Culture Capital and UNESCO site, the Pleistocene Gravina Calcarenite is the main natural stone used to build. This gives a unique aspect to the ancient part of the town called Sassi. It's an awesome example of a rock-cut settlement where architecture is fit to the geological features. Unfortunately, constructions are currently in a deteriorated state and it is possible to see on the 'calcareous tuffs' several degradation morphologies. This work analyses the connection between geological features and alteration patterns in order to obtain useful informations to preserve historical building during the time. A detailed classification of the decay forms, based on a newly defined damage index, has been obtained after investigation of 100 façades considering different types of Calcarenites and evidences obtained on the surface. For each degradation morphology a specific decay degree is defined in relation with evidences on the surface of the façades. In addition, a detailed analysis of stones of the San Pietro Barisano church allowed obtaining information on structural, compositional and textural features of Calcarenite, and the related degradation morphologies. © (2017) by the International Measurement Confederation (IMEKO). All rights reserved.