SURVEY, STRATIGRAPHY OF THE ELEVATIONS, 3D MODELLING FOR THE KNOWLEDGE AND CONSERVATION OF ARCHAEOLOGICAL PARKS: THE CASTLE OF AVELLA

Abstract. The site of Avella is a precious example of ruined medieval fortification with territorial and landscape values. The width and vulnerability of its masonry remnants require a systematic survey and physical investigation, necessary to any preservation and enhancement strategy planning, so far, not yet extended to the fronts of the fortress and the two walled lines. The understanding of the process, scientifically based, which over time has led the buildings to the present state of fragmentation has the same need. Obtain with expedited methods and customary instruments a photogrammetrically controlled survey, the stratigraphic study of the castle elevations and the processing of a photo-based 3D model is therefore the aim of the paper. Carried out on an interdisciplinary basis, it comes from the extension of the outcomes of a didactic workshop in master’s degree courses in Architectural Survey and Restoration Design, held in 2018. The surveying procedure with the drone proved to be the most suitable, also for the possibility of an expeditious and cheaper measurement phase compared to other surveying methods. The results comprise the fortress georeferenced ortho-photomosaic and its photo-based 3D model, then exported both as a point cloud and a 3D mesh. The workshop also implemented topography and terrestrial photogrammetry procedures, such as to be compared with the previous one.