Kunstharzpressholz zur Verstärkung von Brettschichtholz

Abstract

Compressed laminated wood for the strengthening of glued laminated timber Glued laminated timber girders were investigated, which were strengthened with compressed laminated wood at the tension lamella and optionally also at the compression lamella to increase load-bearing capacity and stiffness. Compressed laminated wood is a wood composite consisting of beech (Fagus sylvatica) veneers, which are impregnated with phenol-resorcin resin. Compressed laminated wood possesses a YOUNG's modulus of more than 20 000 N/mm 2 and a bending strength of more than 200 N/mm 2 , which is compared to glued laminated timber GL24h a doubling and a tripling, respectively. The strengthening of the GL24h girders with compressed laminated wood led to a doubling of the bending capacity and to an increase of stiffness of about one third compared to plain GL24h girders with the same cross section. Moreover, the joint of glued laminated timber and compressed laminated wood was exposed to wetting-drying cycles to investigate the durability. Partly impregnated compressed laminated wood absorbed a lot of moisture and swelled heavily, but still less than plain beech wood. Thus, this material is only recommendable for the service classes 1 and 2. Completely impregnated compressed laminated wood showed only very low moisture uptake and swelling and can be applied also in service class 3.

Evaluation of Mechanical Properties of Reinforced Poplar Laminated Veneer Lumber

“…In addition, many other methods of reinforcing LVL have been studied, such as veneer densification using impregnation, and adding bamboo veneer into LVL. All of these methods have been shown to be effective at reinforcing the mechanical properties of LVL (Zhu et al 2005;Liu et al 2007;Liu et al 2009;Haller et al 2015).…”