The aim of this paper is to provide answers to some questions of the archaeologists and leaders of cultural heritage agencies in charge of structures affected by structural problems and instabilities with emphasis on the Arles roman aqueduct in the South of France. The modeling is performed with NSCD discrete element method. The 3D geometric decomposition of the two structures is realistic and is obtained by a conversion from (DXF) CAO format to LMGC90 discrete element code which is dealing with the NSCD method. A comparison with continuous modeling shows the unique possibilities of discrete modeling to account for observed failure phenomena on the real structures.