AIC's 46th Annual Meeting

In 2012, the Georgia O’Keeffe Museum concluded a year-long, three venue touring exhibition of 75 canvas works of art by Georgia O’Keeffe. Despite the clear evidence from courier logs and temperature, humidity and shock data loggers that no harmful shock or environmental extremes had occurred in transit, post exhibition examinations and imaging revealed that several works had suffered both new and existing crack and interlayer cleavage propagation. While museum conservators understood that physical and mechanical damage to art in transit is cumulative, existing literature suggested that repeated exposure to low amplitude, randomly generated vibration accelerations commonly encountered in fine art transport trucks and airplanes should pose little danger to works of art. Yet conservators discovered a strong correlation between the number of miles of motor transport with historic and contemporary crack and cleaving propagation in its paintings. Because the museum was traveling its collection far more frequently each decade than it had previously and because that it had no data on the natural frequency of the paintings in its collections, nor an understanding of the vibration frequencies transmitted by art transport vehicles or attenuated by fine art crates, it began a study to use calibrated three axis accelerometers, laser displacement meters and laser vibrometers to gather a more complete understanding of the mechanics of transit vibration induce- damage in art transit. The museum used acceleration measurements, displacement measurements, discrete cosine transform and Fourier fast transform to understand the power distributions of both facsimile paintings and, ultimately collection paintings, as well as truck beds, walls and various crating and cushioning methods. The findings fundamentally changed the museum’s understanding of vibration induced damage to canvas paintings, the vibration spectral power distribution of fine art transport vehicles, and the successes and failures of framing, backing, crating and loading methods to attenuate vibrations across damage- sensitive frequencies. The presentation will summarize the methods, results, canvas movement visualizations and conclusions of the 5 year study.  The tendency of traditional foam-cushioned wood crates to generate additive interference and amplify canvas displacement excursions at frequencies surrounding the natural frequency of the paintings suggests the need for new engineering approaches for the protection of canvas paintings during transit. Likewise, the vibration damping effects of sealed frame backings and glazing in frames will also be described.