The masonry of the Terme di Elagabalo at the Palatine hill (Rome). Survey, analysis and quantification of a roman empire architecture

The NE slopes of the Palatine and the Colosseum valley area have been the place of a long archaeological research; here the continuous urban development produced an overlap of architectural complexes distributed over time. The huge amount of archaeological documentation produced during research is managed by an intra-site GIS. For ancient walls analysis we have introduced the use of image-based-modelling photogrammetry in order to create a very detailed 3D documentation, marked by an increasing and progressive high-level-autopsy, linked to a DBMS dedicated to ancient structural features. In this procedure we also decided to compare two different approaches to check results of both: one based on taking brick measures directly by hand, the other taking same measures on photogrammetric elaborations by GIS. Through this methodology, counting measures and dimensional aspect of wall facades features, we can evaluate specific aspects of the ancient construction yards for each period; we can also refine the chronological sequences of the architectures and verify the contextual relationships of the surrounding buildings in order to formulate wide-ranging reconstructive hypotheses