Using a digital X-ray imaging device to measure the swelling coefficients of a group of wood cells

Overview & Synopsis

An experimental device has been developed to perform numerical X-ray images by direct projection of samples made of a group of wood cells. This device consists of a micro-focus X-rays source, a scintillator and a cooled CCD camera. The dimensions are adapted to anatomical structure of wood. A speci®c climatic chamber has been conceived to control the moisture content of the sample. Experiments consist in imaging the sample at different humidity conditions. After pre-processing, a program compares two images and allows the bidimensional strain field to be determined. The shrinkage coef®cients obtained by this protocol are representative of the unrestrained shrinkage properties of the wood sample.