Experimental Determination of the Mechanical Properties of The Night Watch Canvas using Micro-Tensile Testing

The determination of the structural condition and the mechanical properties of The Night Watch are of high importance when it comes to defining conservation treatments and future preservation policies for the painting. To this end, an advanced minimally-invasive experimental investigation of the mechanical properties of the canvas is performed. Due to its significant contribution to the structural support to the painting, the study principally focuses on the lining canvas, which was applied to the back of the painting in 1975. Considering the limited availability of samples, micro-scale mechanical tests are carried out on single cellulose fibers that have been extracted from the canvas threads.
The strength, the stiffness and the fracture strain of the fibers are robustly and accurately measured using a recently developed micro-tensile testing methodology. This information can then be extended to larger scales (thread and thread-network) to provide insight into the long-term stability of the lining canvas and to ensure that the load introduced with the spring-tensioning system will be kept well below the failure threshold of the lining canvas.