Understanding the Moisture Induce Fatigue Damage in Panel Paintings: A Methodological Approach for Quantifying the Role of Preparatory Layers in the Overall Response

Aurand, A., Gauvin, C. , Jullien, D. and Young, C. (2016) Understanding the Moisture Induce Fatigue Damage in Panel Paintings: A Methodological Approach for Quantifying the Role of Preparatory Layers in the Overall Response. ICOM-CC Joint Interim Meeting on Physical Issues in the Conservation of Paintings: Monitoring, Documenting and Mitigating, Paris, France, 29-30 Sep 2016.

Abstract

Th is paper presents the develop ment of an experimental methodology for quantifying the moisture related response of preparatory layer s in the overall behaviour of panel paintings . This research to date h as focused on 14th c entury Southern European panel s. Those consist of wooden boards on which preparatory layers , including size, canvas and ge s so, have been applied to receive the painted image. Due to the hygroscopicity of some of the constituent materials, r epeated fluctuations in relative humidity have been associated with the cracking of prepar atory layers. Known as the fatigue damage, t his may cause further delamination and eventually a loss of the image. Understand ing this mechanism and the long - term consequences will allow conservators to anticipate deteriorating conditions and inform stan dards of environmental control. When subjected to fluctuating RH, the differential expansion and contraction occurring between gesso an d wood have been held responsible for the fracturing of the gesso . However, panels are multi - layer composites often comprising several types of preparatory layers . As complex composites , a methodology is required to characterise the parameters involved in the hygro - mechanical response causing damage. T esting included Beam Identification by Non - destructive Gr ading, Digital Image Correlation (DIC ) under hygro - loading, four point bending and tensile testing to monitor and analyse strain fields induce in selected historical preparatory layers coated on wood. Quarter - sawn samples were cut from a seasoned board of white poplar ( Populus alba L.) from the region of Florence , Italy . Technical examination and historical source were used to select d ifferent formu lations of gesso, thicknesses and layer structure . Tests were conducted on composite samples and single layers. Recording deformation states within the samples using DIC proved successful and allowed for a characterisation of key parameters involved in t he moisture - induced damage to some extent . In c ombining analytical testing i t was possible to identify heterogeneous behaviours depending on the type of preparatory layers . Results also suggested that predicting future damage by mechanically replicating en vironmental fatigue should be investigated.

• Item Type: Conference or Workshop Item
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Gauvin, Dr Cecilia and Young, Professor Christina
• Authors: Aurand, A., Gauvin, C., Jullien, D., and Young, C.
• Subjects: N Fine Arts > ND Painting; Q Science > Q Science (General); T Technology > TJ Mechanical engineering and machinery
• College/School: College of Arts & Humanities > School of Culture and Creative Arts > History of Art