When Conservation Meets Engineering: Predicting the Damaging Effects of Vibrations on Pastel Paintings

Pastel paintings are one of the most fragile types of objects of art. When handling loan requests, conservators lack scientific data to assess the risk for damage in transport, and thus for making decisions whether they can be transported. A research project was initiated in 2014 to investigate the effect of vibrations on the condition of pastel paintings, and to determine under what conditions they can be transported with minimum risk for damage due to vibrations. The initial results of this work indicate that the vibration behaviour of pastel paintings is a cumulative one and can be dealt with as an issue of fatigue. If failure is defined as a given level of unacceptable visual loss of pastel, it has been shown that higher stress amplitudes lead to shorter lives to failure than lower stress amplitudes. The use of a fixative appears to prolong fatigue life. There also appears to be a fatigue limit for freshly drawn pastels without fixative. This study highlights the synergism between typically non associated fields of research, in this, art conservation and the fatigue failure of materials.