MODELLING HISTORIC SITES AND MONUMENTS IN 3D HERITAGE INFORMATION SYSTEMS BY COMBINING AERIAL AND ARCHITECTURAL PHOTOGRAMMETRY

TC V-8 Site recording and modelling TC V-10 World Cultural heritage and information systems KEY-WORDS: Architecture, CAD, Database, Modelling, Spatial database, Topology, Urban objects The modelling of 3D objects in surveying and particularly of historic monuments is generally mainly based on geometry. Our aim is to extend the modelling approach of 3D complex geometric monuments by integrating the semantic structure in combination with geometry. We propose a method for 3D geometric, topologic and semantic modelling of sites and monuments which is linking aerial and architectural photogrammetric restitution. The elements to be modeled are decomposed into different "semantic concepts " that include a semantic structure. One of the objectives is to automate the reconstruction of objects corresponding to semantic concepts. The Topographical Information System of the area (obtained by aerial photogrammetry) and the Architectural Information System of the monument (obtained by terrestrial photogrammetry), is created by this first step and then completed with the semantic details. The data acquisition is realized by using a low cost PC and Windows based system for digital stereophotogrammetry 'TIPHON ' developed at ENSAIS-LERGEC, interconnected to the CAD-GIS software package Microstation/Geographics and the ACCESS relational database. Our method has been tested on two projects:- the first one is in Cairo (Egypt) in the Sayeda Zienab area around the aqueduct El Ghuri;- the second one is located in Strasbourg and applied to buildings constructed at the end of the last centur