ISO 8970:2020 Timber structures — Testing of joints made with mechanical fasteners — Requirements for timber density

ISO 8970:2020 Timber structures — Testing of joints made with mechanical fasteners — Requirements for timber density.
1 Scope
This document specifies a method based on density, for the selection of pieces of wood used in determining the strength and stiffness properties of joints between members of structural timber made with mechanical fasteners. It is intended to be used in conjunction with a test standard specifying a test method.
ft is assumed that the wood pieces are conditioned to the relevant conditions, that the wood density is normally distributed and that any deviations are reported.
This document is applicable only to specimens of structural timber.
NOTE It is emphasized that the wood density is only one of the properties that can influence the strength of
a joint. Other relevant properties are, for example, growth-ring size and orientation, toughness and hardness.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 13061-2, Physical and mechanical properties of wood — Test methods for small clear wood specimens — Part 2: Determination of density for physical and mechanical tests
3 Terms and definitions
No terms and definitions are listed in this document
ISO and IEC maintain term inological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at httpswww.iso.org/obp
— I EC Elect ropedia: available at http://www.electropedia.org/
4 Symbols
p is the density of a wood piece, expressed in kilograms per cubic metre.
5 Wood sampling method and requirements
5.1 General
The wood shall be at equilibrium at a relative humidity (RH) of (65 ± 5) % and a temperature of (20 ± 2) °C at the time of testing. It shall be reported whether the wood was dried or moistened during the conditioning.
NOTE The moisture content at equilibrium is lower when reached by moistening than if reached by drying, which can affect the test results. The product test standard can specify if the equilibrium condition is to be reached through drying.ISO 8970 pdf download.