Your search resulted in 7 documents.
Moisture correction for ultrasonic MOE measurements above fibre saturation point in Scots pine sapwood
2006 - IRG/WP 06-20333
There is a high correlation between methods for dynamic modulus of elasticity (MOEdyn) and static modulus of elasticity (MOEstat). MOEdyn methods have been found sensitive to detect early stages of decay and may be seen as an option for non-destructive wood durability testing. As the MOEstat measurements do not change after reaching the fibre saturation point, the uncorrected MOEdyn data from ultr...
E Larnøy, G Alfredsen, H Militz
The use of modulus of rupture and modulus of elasticity in natural durability testing
1997 - IRG/WP 97-20117
Losses in weight, losses in bending strength and changes in elastic behaviour were assessed in a fungus cellar test with beech wood stakes (Fagus sylvatica). Results were gained after 8, 12, 16 and 20 weeks resp . The outcomes show, that the non-durable species beech is very rapidly attacked by fungi and loses up to 60% of its initial bending strength even within the first 8 weeks. Earlier researc...
L Machek, H Militz, W Gard
The influence of the location of a wood defect on the modulus of elasticity determination in wood durability testing
2004 - IRG/WP 04-20287
This study investigates the influence of the location of a wood failure in stakes upon elastic changes observed in beech specimens with the resonance vibration technique. Natural failures were simulated by artificially created defects at different locations of the test stake. The results indicate that the location of an attack in a stake is important for the measurement outcome. When the attack is...
L Machek, H Militz
A dynamic approach to assess the modulus of elasticity in wood decay testing
1998 - IRG/WP 98-20139
In this study, the changes in elastic behaviour and mass losses of different hardwood and softwood species exposed to decay in a laboratory soil tests were assessed. Wood decay was monitored using different assessment methods, namely: mass loss and changes in elastic behaviours (MOE) determination. Elastic changes were determined by static and dynamic methods, for the latter, acoustic technique wa...
L Machek, H Militz, R Sierra-Alvarez
A non-destructive testing technique for wood poles
1987 - IRG/WP 2293
A method has been developed to evaluate the stiffness and condition of a wood pole based on structural dynamics. This paper describes the results of tests performed on nearly 200 wood utility poles across Western Canada. A high correlation exists between the dynamic non-destructive test and direct mechanical tests. The need for an accurate non-destructive testing technique is demonstrated by the f...
W M Murphy, D E Franklin, R A Palylyk
Acoustic technique for assessing decay in preservative treated wood
1998 - IRG/WP 98-20138
This study investigated the suitability of vibration techniques to assess the performance of wood preservatives in ground contact. Small stakes (10 x 5 x 100 mm3) of treated and untreated Scots pine sapwood were exposed to decay in lab-scale terrestrial ecosystems. Tests were conducted using three different soils including a garden compost soil, and soils obtained from a test field and a conifer f...
L Machek, M-L Edlund, R Sierra-Alvarez, H Millitz
Towards a microactuator-sensing network for the structural health monitoring of wood
2023 - IRG/WP 23-50380
Timber structures decay over time with degradation in their structural integrity. Changing environmental conditions, varying loads, exposure to moisture or insect attacks lead to changes in their vibrational response behaviour. Here we present a low-cost device used as a triggered exciter to enable the monitoring of the structural integrity of timber bearers or even power poles in electricity netw...
S Oberst, S Sepehrirahnama, C Nerse, Z Brodzeli, J C S Lai, M Mankowski, T Atkinson, R Arango, G Kirker, T Evans