Skip to main content
Research article - Peer-reviewed, 2021

Embedment properties of thermally modified spruce timber with dowel-type fasteners

Van Blokland, Joran; Florisson, Sara; Schweigler, Michael; Ekevid, Torbjörn; Bader, Thomas K.; Adamopoulos, Stergios

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

Authors' information

Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology
Florisson, Sara
Luleå University of Technology
Schweigler, Michael
Linnaeus University
Ekevid, Torbjörn
Volvo Construction Equipment
Bader, Thomas K.
Linnaeus University
Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology

UKÄ Subject classification

Wood Science

Publication Identifiers

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

URI (permanent link to this page)

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