Anastylosis

Anastylosis, written anastilosis in Turkish, is the re-erection of a collapsed or scattered structure largely from its own original pieces. Fragments lying on the ground, such as column drums, capitals, architrave blocks or voussoirs, are identified one by one, their original positions are established and they are set back in place. The method is used mostly on ancient buildings and archaeological sites.

Principles of anastylosis

International conservation practice accepts anastylosis as one of the few legitimate forms of re-erection, but under strict conditions:

• Most of the structure must consist of original pieces; new material is used only to hold the pieces together and make the structure safe.
• Any new parts must be clearly distinguishable from the original.
• Every piece’s position must rest on evidence: matching break surfaces, cramp sockets, tool marks and dimensions.
• The method must not harm the original pieces, and connections should be reversible wherever possible.

Documentation, 3D models and anastylosis

The work begins by numbering and measuring every fragment on site. Once each block is captured in 3D through photogrammetry and laser scanning, pieces can be tested and matched digitally, so the fit of each block is checked before heavy stones are moved on site. This digital trial also becomes the basis of the restitution proposal. Scaled 3D architectural modeling of this kind clearly shows heritage boards which parts will be re-erected and which are original or new.