JAIC 1990, Volume 29, Number 1, Article 4 (pp. 45 to 76)
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Journal of the American Institute for Conservation
JAIC 1990, Volume 29, Number 1, Article 4 (pp. 45 to 76)

DETERIORATION OF SURFACES EXPOSED TO ENVIRONMENTAL CHANGES

GUSTAV A. BERGER, & WILLIAM H. RUSSELL


ABSTRACT—This research into the mechanical behavior of fabric-supported paintings goes back to the late 1960s when G. Berger's investigations culminated in the development of a new lining system for paintings (BEVA) (Berger 1972, 1975). Lining of the Atlanta Cyclorama required further research, which, since 1980, has been done jointly with W. H. Russell (Berger 1981). In order to measure the responses of canvas paintings to controlled changes in the environment, the authors have built a Biaxial Stress Tester for Stretched Canvas, described under “Test Equipment.” Numerous samples of old and new, painted and unpainted linen canvas have been tested under controlled environmental conditions of 0–50C and 5–100% RH, and their stress changes have been recorded (Russell and Berger 1982; Berger and Russell 1984, 1986, 1988). The resistance of the samples to controlled dimensional changes (Modulus of Elasticity, “E”) has also been measured within the limits of the above environmental conditions.Since June 1984, a wealth of information has been collected with the help of automated data logging. Based on these findings, a working model of the decay of canvas paintings was developed (Berger and Russell 1984, 1986). Since all outer surfaces of solid bodies may be considered stressed membranes, these investigations have provided new insights into the process of aging and decay of all surfaces exposed to environmental changes. Investigations into the effects of some artists' techniques and certain conservation treatments have already been published (Berger and Russell 1986, 1987, 1988). Because not all of the above publications are readily available, they have been summarized in this paper, supported by actual examples and accompanied by practical applications (Berger 1983, 1984). Recent findings were incorporated to update, confirm, and elaborate on previously published material wherever necessary.

Article Sections:

1. INTRODUCTION
2. MEASUREMENTS OF CANVAS TENSION
3. STRETCHING A CANVAS
4. THE IMPORTANCE OF TENSION FOR CANVAS PAINTINGS
5. STIFFNESS, RESISTANCE TO DEFORMATION (MODULUS “E”)
6. STRESS-VALVES OR DEFORMATION-TRAPS
7. EFFECTS OF CYCLING ENVIRONMENTAL CONDITIONS ON PAINT FILMS
8. CYCLING ENVIRONMENTAL CONDITIONS AND DISCONTINUITIES IN THE STRUCTURE OF THE PAINTING
9. PROTECTION OF PAINTINGS UNDER ADVERSE ENVIRONMENTAL CONDITIONS
10. PRACTICAL EXAMPLES SUPPORTING THE NEW MODEL OF PAINT DECAY
11. CONCLUSIONS
12. SUMMARY
13. TEST EQUIPMENT
a: References , Author Information
Entire Article

Copyright 1990 American Institute for Conservation of Historic and Artistic Works