Finite Element Modeling of Vibrations in Canvas Paintings

Abstract

Preventing vibration damage from occurring to valuable and sensitive canvas paintings is of main concern for museums and art conservation institutions. This concern has grown in recent years due to the increasing demand of paintings for exhibitions worldwide and the concomitant need for their handling and transport. The vibration of the canvas can produce progressive delamination of cracked paint in aged paintings which may cause paint loss after repetitive vibration exposure. In the cultural heritage world, there is limited knowledge about the vibration behavior of the canvas and its relation with the damage produced in the paint. The goal of this investigation was to improve this understanding about the vibration behavior of canvas paintings through the use of finite element modeling. A model was developed with the capability of predicting the natural frequencies and mode shapes of canvas paintings, and providing a fundamental understanding of the parameters that influence their dynamic behavior. Canvas paintings exhibit vibration behavior of thin orthotropic plates dominated by the tension and mass of the canvas with negligible bending stiffness. The model was verified and optimized experimentally using a specially designed vibration testing system for canvasses, showing differences within 5% between the first two predicted and measured natural frequencies. Follow-up work to study the non-uniform biaxial tension and to improve the canvas textile material model is needed in order to improve the accuracy of the vibration model for higher modes. Further research is also required to better understand the delamination of paints due to vibration (cyclic) loading. Combined with this model, this will better assist museums and conservators taking precautions and making decisions about vibration exposure and tolerable levels.