Les caractéristiques du bois de Peuplier

in Le peuplier en Wallonie (2003)

The poplar wood has been known and used for a very long time. However, it has been systematically studied only since the end of the second world war, probably because of its reduced presence in the ... [more ▼]

The poplar wood has been known and used for a very long time. However, it has been systematically studied only since the end of the second world war, probably because of its reduced presence in the forests. An intuitive use of the poplar existed already among our ancestors but the study of its macro- and microscopic properties has directed it to more specific uses. The comprehension of its physical and mechanical properties led to a better knowledge of its behaviour during the various phases of transformation and helped to forecast its evolution when used, taking into account its natural longevity and the eventual presence of defects appearing on the trees and in the wood. In current poplar cultivation, all these characteristics must be considered to fix the criteria of selection taking into account the quality of the wood and its capability for transformation. The clonal production of poplars offers the transformation industry a raw material relatively homogenous in terms of technological properties, form and dimension. Nevertheless, each cultivar can differ in one or several of its characteristics. [less ▲]

Comparison of basic density and longitudinal shrinkage in tension wood and opposite wood in young stems of Poplar (P. euramericana cv “ Ghoy ”) when subjected to a gravitational stimulus

in Canadian Journal of Forest Research = Journal Canadien de la Recherche Forestière (2001), 31(10), 1676-1683

In a green house, under controlled conditions, young shoots, taken from poplar cuttings (P. euramericana cv “ Ghoy ”), were artificially inclined in order to quantify the modifications of physical ... [more ▼]

In a green house, under controlled conditions, young shoots, taken from poplar cuttings (P. euramericana cv “ Ghoy ”), were artificially inclined in order to quantify the modifications of physical properties induced by a gravitational stimulus. At the end of the growing season, basic density and longitudinal shrinkage were measured on very small samples taken from pure tension wood tissue observed on the upper face of the inclined axis and compared with opposite wood tissue, free of gelatinous fibers, developed on the opposite lower face. In a second step, shoots bend at two different lean intensities were analyzed. On young poplar wood, gravitational stimulus was found to have a significant effect on physical properties. Relations between basic density and longitudinal shrinkage are different depending on the types of wood considered. Shrinkage appears more sensitive to lean intensity in the range considered here [less ▲]

A propos du bois de tension des peupliers

in Maes, Freddy; Beeckman, Hans (Eds.) Annales Sciences Economiques - Vol 25 - Wood to survive (1999)

Etude technologique de la valorisation par lamellation de chênes indigènes de petites dimensions

in Bulletin des Recherches Agronomiques de Gembloux (1990), 25(3), 313-328

The authors have examined the technological feasibility of laminating small sized logs (girth at breast height between 70 and 150 cm) of European oaks (Quercus robur L. and Quercus petraea LIEBL.). This ... [more ▼]

The authors have examined the technological feasibility of laminating small sized logs (girth at breast height between 70 and 150 cm) of European oaks (Quercus robur L. and Quercus petraea LIEBL.). This technique allows indeed to produce from a low grade raw material a product able to compete with solid wood of first choice. The manufacturing of window frames has been taken as an example of the use of laminated oak. The observed output from the sawing of the experimental material seems to point out that only the logs belonging to the girth categories between 105 and 145 cm are really able to be upgraded by this process (output ranging from 19 % up to 28 %). The shrinkage measurements show that the processed raw material is characterized by a low dimensional stability. The effect of the wood species and the kind of glue on the mechanical behaviour of the product has been investigated. Oak has a lower bending strength than merbau but higher than meranti or larch from Oural. Considering the different glues used for this experiment, it has been observed that they give in "dry state" a higher shear strength than solid wood. However, moisture induces to a variable extent a strength loss for all the compared wood adhesives. [less ▲]