Relation between fracture characteristics and moisture content along longitudinal direction in a naturally drying Scots pine

Abstract

The mode I critical stress intensity factor of a Scots pine beam was studied in the tangential-radial crack propagation system. The beam was naturally dried in the lab enviroment following a year and a half-long exposure to the harsh climate of Trondheim in Norway. A comparison between critical stress intensity factor values obtained by means of experimental and theoretical approaches were made. Finite Element analysis along with the critical stress intensity factor tests were carried out to identify the values in the former datasets, while to create the latter datasets, a modified relation, on the basis of The ASTM 399–20 Standard, was propsed. The values in the above mentioned datasets, were in close correspondence together. Furthermore, the moisture content within the radial and longitudinal directions of the beam using the relative humidity and response time of the samples was studied. Finally, the relation between the moisture content and the critical stress intensity factor along the length of the beam was investigated and compared with the reported data in the literature. It was found that the pre-experimental conditioning of the wood and crack directionality system had a considerable impact on the values of critical stress intensity factor.