Issue 40

M. Mentzini, Frattura ed Integrità Strutturale, 40 (2017) 95-107; DOI: 10.3221/IGF-ESIS.40.09 106 The present paper reveals the special skill, imagination and creativity of the scientists in order to determine the sequence of actions which must be undertaken to join the pieces forming the drum and to apply the proper reinforcement so as the structural integrity of the drum as a whole to be achieved. In this way in many cases the same reinforcement expands to cover the structural needs of another section. Moreover, the problems arising due to the irregular shape of fracture’s planes or the discontinuities in marble mass, could be solved by changing the number, the diameter or/and the place of the reinforcement bars and keeping in the same time the produced stress field constant. If internal reinforcement bars can not be used (so as to be unseen) because of the inability of the adjustment or the maintenance of the proper anchorage length, alternative solutions are invented, such as: the insert from the sides (which will be covered when the drums will be placed back in their initial position on the column) or from areas of the drum’s view, which exhibit marks of decay, having lost their original ancient surface. Even the mortises of N. Balanos’ restoration are used to insert bars or to place “Π” and double “T” shape titanium connectors to contribute to the stress required and also to minimize further loss of the authentic material. As it was pointed out before, the previous restoration by the engineer N. Balanos changed in many cases the original exact position of the drums. During the structural intervention of the dismantled pieces the access to their fractured areas and the verification of coincidence between different members’ fractures, reveal their original position and identify whether the certain drum belongs or not to a certain position on the column. Thus by these observations the original exact position of the drums was also confirmed in perfect agreement with the findings of the Architectural study [16]. R EFERENCES [1] Mentzini, M., Report of the project of the Parthenon’s North Colonnade restoration, Ancient members’ structural intervention: Columns and architraves. The Drums, vol. A, Archives of the General Direction of Antiquities and Cultural Heritage (2015). [2] Zambas, C., Ioannidou, M., Papanikolaou, A., The use of titanium reinforcements for the restoration of marble archi- tectural members of Acropolis Monuments, Proc. IIC Congress on Case Studies in the Conservation of Stone and Wall Paintings, Bologna: The International Institute for Conservation of Historic and Artistic Works, (1986) 138-143. [3] Mentzini, M., Joining together architraves and drums of Parthenon using titanium: A new approach, Proc. 5th Int. Symp. for the Restoration of Acropolis Monuments, Athens: Committee for the Preservation of the Acropolis Monuments (2002) 233- 242. [4] Exadaktylos, G.E., Vardoulakis, I., Kourkoulis S.K., Influence of nonlinearity and double elasticity on flexure of rock beams - II. Characterization of Dionysos marble, International Journal of Solids & Structures, 38 (2001) 4119-4145. [5] Kourkoulis, S.K., Exadaktylos, G.E., Vardoulakis I., U -notched Dionysos-Pentelicon marble in three point bending: The effect of nonlinearity, anisotropy and microstructure, International Journal of Fracture, 98 (1999) 369-392. [6] Kourkoulis, S.K., Prassianakis, I., Agioutantis, Z., Exadaktylos, G.E., Reliability assessment of the NDT results for the internal damage of marble specimens, International Journal of Material and Product Technology, 26 (2006) 35-56. [7] Mentzini, M., Drums’ fracture-The example of the 6th column of Parthenon’s Pronaos, Proc. 8 th Int. Sym. on the Conservation of Monuments in the Mediterranean Basin, M. Koui & F. Zezza (eds.), Patras, Greece (2010) 56-57. [8] Balanos, N., The Restoration of the Acropolis monuments, Editor S.N.Taroussopoulos, Athens, (1940) [9] Korres, M., Bouras, H., Study for the restoration of the Parthenon, Athens: Ministry of Culture of Greece, Committee for the Preservation of the Acropolis’ Monuments (1983). [10] Mentzini, M., Structural interventions on the Acropolis monuments, Newsletter of the Acropolis restoration service of the Ministry of Culture of Greece, 6 (2006) 15–18. [11] Zambas, C., Structural problems of the restoration of the Parthenon, Vol.2a, Athens: Committee for the Preservation of the Acropolis Monuments (1989). [12] Zambas, C., Structural problems of the restoration of the Parthenon, Vol.3b, Athens: Committee for the Preservation of the Acropolis Monuments (1994). [13] Psycharis, I.N., Lemos, J.V., Papastamatiou, D.Y., Zambas, C., Papantonopoulos, C., Numerical study of the seismic behaviour of a part of the Parthenon Pronaos, Earthquake Engng. Struct. Dyn., 32 (2003) 2063-2084. [14] Psycharis, I.N., Seismic Response of Classical Monuments with Fractured structural elements, in “Fracture and Failure of Natural Building Stones”, Stavros K. Kourkoulis (ed.), Springer, Berlin (2006) 239-255. [15] Mentzini, M., Columns and architraves: the process of structural intervention, in: Interventions on the Acropolis monuments 2000-2012, The completed programmes, Proc. 6 th Int. Symp. for the Restoration of Acropolis Monuments, Athens: Committee for the Preservation of the Acropolis Monuments (2013) 1-24.