Abstract

This study investigates the effect of thermal modification, ThermoWood Thermo-D treatment versus no treatment, on the embedment properties of Norway spruce timber (Picea abies [L.] Karst.) with dowel-type fasteners. The test specimens were reinforced to prevent splitting of the wood. The influence of density, load direction, test specimen configuration (full hole versus half hole), moisture content, gauge points and calculation method were also evaluated. Thermal modification primarily affected the embedment strength parallel to the grain, which was ∼ 25% higher after thermal modification, mainly due to the change in physical properties because of the treatment, i.e. the lower equilibrium moisture content. The influence of the investigated parameters on embedment properties of thermally modified spruce followed similar trends as for unmodified spruce. It was for example seen that the density–embedment strength relationships still hold after the treatment despite the decrease in density and the increase in embedment strength parallel to the grain. However, after thermal modification, the influence of load direction on embedment strength was ∼30% larger and the influence of calculation method (yield versus ultimate strength) on embedment strength perpendicular to the grain was ∼10% smaller.

Keywords

ASTM D 5764-97a; embedment stiffness; embedment strength; EN 383; foundation modulus; full-hole test; half-hole test; Norway spruce; ThermoWood®

Published in

Construction and Building Materials
2021, Volume: 313, article number: 125517

SLU Authors

• Van Blokland, Joran

  • Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences
    

• Adamopoulos, Stergios

  • Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Wood Science


Publication identifier

DOI: https://doi.org/10.1016/j.conbuildmat.2021.125517

Permanent link to this page (URI)

https://res.slu.se/id/publ/114327