Principles of the present interventions
A general principle of the works is to carry them out on the basis of decisions taken as objectively as possible, with transparency in all phases. These goals are achieved primarily by means of an interdisciplinary approach to the interventions during the phases of study and application, the publication of general and specialized studies for the restoration of the monuments prior to the actual interventions, their submission as top-level studies to a procedure of multiple assessment and then the final publication of the works.
The International Conferences of specialists held at regular intervals for exchange of opinion about the various proposals for interventions on the monuments and other special subjects, comprise a particularly important feature of the works. The interventions, in themselves, are conducted in the spirit of the Venice Charter (1964), the internationally accepted framework of principles codifying the requirements for the restoration of monuments. The following principles were formulated particularly for the monuments of ancient Greek architecture, and stem from the actual building system of the monuments of the classical period.
Compliance with the above theoretical principles leads to specific choices in planning structural interventions on the Acropolis monuments, which can be summarized as follows:
The method of the interventions
In cases of severe damage the area of the monument affected is dismantled. The process of dismantling includes the removal of rusted reinforcements and filling material.
After the members are removed, they are structurally restored in the laboratory. New Pentelic marble is used wherever supplements are necessary. To make the supplements, a cast is first made of the missing parts, and using a pointing device the points marked are transferred from the cast to the new marble. After completion, the supplement is joined to the ancient marble with titanium reinforcements and white cement mortar. Diameter and depth of the titanium rods are determined on the basis of structural efficiency. The sockets for the titanium reinforcements never penetrate the outer surface of the members.
After they have been restored, the architectural members are reset in their original locations and joined by means of titanium clamps and dowels. In this resetting of the members, geometrical distortions in the area being reassembled are removed, so that the original appearance of the building is attained to the extent possible.
In addition to dismantled architectural members, scattered ancient members that have been recognized as belonging are also reset in their original or a corresponding position. In a few cases, for reasons of stability, it may be preferable to set a few architectural members made entirely of new marble rather than using ancient members restored with new marble that are preserved in fragmentary condition.