An experimental study on restoration technique for the Acropolis of Athens: developing the experimental set-up for pull-out testing of titanium bars embedded in marble blocks

Dakanali, Ioanna; Marinelli, Aikaterini

Abstract

The present work aims at investigating the mechanisms activated during the extraction of titanium bars from a marble volume (pull-out phenomenon), used for rejoining fragmented marble structural members at the monuments of the Acropolis of Athens. The restoration protocol includes the insertion of threaded titanium bars into pre-drilled holes in the body of the structural members. The adhesion between marble and bars is achieved by an initially liquid cementitious material. There are two main aspects on which this project focuses. Firstly, the weak link of the marble-cement-titanium complex, the marble-cement interface, is inaccessible for traditional sensing techniques. In this context, the Acoustic Emission technique is employed in order to detect failure and damages at the interior of the complex. Secondly, the experimental specimen and procedure should simulate the same stress conditions in which all three phases within the marble-cement-titanium complex are under, while the structural member is in service. For this purpose, two modified tests are proposed aiming at efficiently simulating the bars’ behavior as they are sliding through a marble epistyle. The new tests achieve promising results with regards to keeping the examined surface between bars and marble free from the parasitic stresses caused by the experimental set-up.

Citation

Dakanali, I., & Marinelli, A. (2019). An experimental study on restoration technique for the Acropolis of Athens: developing the experimental set-up for pull-out testing of titanium bars embedded in marble blocks. Frattura ed Integrità Strutturale (Fracture and Structural Integrity), 13(50), 370-382. https://doi.org/10.3221/IGF-ESIS.50.31

• Journal Article Type: Article
• Acceptance Date: May 10, 2019
• Online Publication Date: Sep 1, 2019
• Publication Date: Oct 1, 2019
• Deposit Date: May 17, 2019
• Publicly Available Date: Jun 26, 2019
• Journal: Frattura ed integrita Strutturale (Fracture and Structural Integrity)
• Print ISSN: 1971-8993
• Publisher: Gruppo Italiano Frattura
• Peer Reviewed: Peer Reviewed
• Volume: 13
• Issue: 50
• Pages: 370-382
• DOI: https://doi.org/10.3221/IGF-ESIS.50.31
• Keywords: Marble; stone monuments; pull-out; restoration; contact interfaces; acoustic emission
• Public URL: http://researchrepository.napier.ac.uk/Output/1810748
• Contract Date: May 17, 2019