On the numerical evaluation of historical stone sculpture artwork restoration

Abstract

Traditionally, the restoration of historical artworks found during archaeological expeditions is based on the experience and artistic feeling of restaurateur as well as on a simplified analyse considering parts of artworks as rigid solids. Taking advantages from the progress of digitising techniques and virtually restoration of artworks, it is now possible to perform advanced (geo)mechanical analysis in order to evaluate the pertinence of alternative restoration solutions. In this paper, two alternative restoration hypotheses were studied for the statue of Neptune of Arles: in one hand, a metallic-insert-based restoration technique and on the other hand, a glue-based restoration. For the insert-based restoration scenario, the (geo)mechanical analysis aims at verifying of general stability and the local resistance of stone, especially at stress concentration zones as well as the optimisation of inserts. For the glue-based restoration hypothesis, firstly the linear fracture mechanic is used to evaluate the stress intensity factors at the tips of eventual glue-flaws. Then a parametric dynamic analysis is performed in order to identify the limits of glue-based restoration to resist typical transport vibration. The results of our analyses show that, unless special dumping devices are used for road transports, the glue-based restoration would fail against tensile stress induced in interfaces due to road vibrations.

Keywords:

• marble
• sculpted artworks
• digitising
• stone interfaces
• insert-based restoration
• glue-based restoration
• stress intensity factor
• dynamics