Two methodologies for the virtual reconstruction of the architectural remains of a Late Roman archaeological site based on the 3D point cloud

Abstract

This paper presents and discusses two approaches to the virtual reconstructions of the architectural remains of the Late Roman site of Umm-al Dabadib, at the outskirts of the Kharga Oasis (Egypt's Western Desert). The dense settlement is clustered around a central building resembling a fortlet. The primary construction material was mudbrick, completed by a few stone elements. Elliptical pitched-brick barrel vaults covered the small rooms that compose the various buildings. The unit of measurement used in the planning and building was the ancient Egyptian (reformed) cubit. The first method adopted to study these remains consists of direct 3D modelling on the photogrammetric point cloud using the parametric approach of the BIM software Autodesk Revit. This process allowed the complete reconstruction of all levels of the well-preserved fort in the settlement center. The second method tested, on the domestic unit in the northwest corner of the settlement, involved 3D modelling of hypothetical original form starting from 2D technical drawings elaborated from the photogrammetric point cloud in its current state and its hypothetical original form. These drawings were used as a reference to model the domestic unit in Rhinoceros software, which is more suitable to model complex shapes, such as typical living room of the local domestic units, covered by two intersecting barrel vaults of different sizes. The complex morphology of the biaxial vaulted system would have been difficult to model with a more rigid software such as Revit. Instead, Rhinoceros allowed recreating the biaxial vault using tools to extrude profiles, subtract and add simpler shapes. The photogrammetric model was used to adapt the reconstruction to accurate measurements.

DOI: https://doi.org/10.20365/disegnarecon.27.2021.6