An analysis of rolling shear of spruce wood by the Iosipescu method

Shearing is an essential deformation in the treatment of mechanical pulp fi bers into a papermaking pulp. Knowledge of the contribution of shear to the fiber treatment during processing can be obtained by measurements on fiber s in the form of wood, in this work, an attempt was made to use the Iosipes cu method for testing wood in rolling shear. Despite the small size of the shear region of interest between notches made in the wood, the results and their dispersion in both the elastic and inelastic ranges were in accordanc e with previous results found using other tasting methods. The stress-strai n relationship was analysed in relation to the specimen's density profiles in the region of interest. Differences in density explained up to 50 % of t he inter-specimen variability in the shear modulus and in the inelastic beh avior. Failure occurred outside the shearing zone in a large number of specimens. Thus the configuration chosen was not adapted In provide for the strength o f wood in rolling shear. This behavior limited the amplitude of the strain that could be reached between the notches.