Abstract
The mechanical properties of timber can be estimated from wave propagation velocity by measuring wave time-of-flight (ToF). However, a time-lag complicates the measurements, which produces an apparent velocity dependency on length and this species and instrument dependent property is also influenced by knottiness. This research is dealing with time-lag determination by different sensor positioning in situ ToF measurements. ToF longitudinal measurements were conducted on 120 90 mm×140 mm specimens of the coniferous species radiata pine, Scots pine, laricio pine and maritime pine. The following commercially available acoustic devices were used: Sylvatest Duo, USLab, and Microsecond Timer. The sensors were arranged for the measurement types “end-to-end”, “on the same surface” and “on opposite surfaces”. ToF data were obtained from the full-length (4 m) specimens and then from the same specimens shortened to 3 m, 2 m and 1 m in length. The in situ procedures of ToF are applicable for a reliable length determination independently from the time-lag (tL) and velocity. The differences observed by end-to-end measurements, with respect to velocity, are below 4.4%. A velocity correction factor can be deduced for each instrument, which is independent of species.
Acknowledgements
Ministerio de Economía y Competitividad, España, Programa Estatal I+D, 2013–2016 (Ministry of Economy and Competitiveness, Spain, State Plan, Research and Development), Proy.: BIA2014-55089-P. Plan Nacional I+D+i 2008–2011, Proy.: BIA 2010-18858 and Mr. Ramón García Lombardero of Structural Timber Laboratory of CIFOR-INIA, Spain, for his technical assistance in this study.
References
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©2017 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Original Articles
- Enzymatic grafting of kraft lignin as a wood bio-protection strategy. Part 1: factors affecting the process
- Enzymatic grafting of kraft lignin as a wood bio-protection strategy. Part 2: effectiveness against wood destroying basidiomycetes. Effect of copper entrapment
- Isolation and characterization of triterpenoids from the stem barks of Pinus massoniana
- Radial distribution of monomeric, dimeric and trimeric norlignans and their polymerization in Cryptomeria japonica heartwood
- Influence of length and sensor positioning on acoustic time-of-flight (ToF) measurement in structural timber
- Calcium phosphate bonded wood and fiber composite panels: production and optimization of panel properties
- Water sorption hysteresis in wood: III physical modeling by molecular simulation
- Characteristics of carbon nanofibers produced from lignin/polyacrylonitrile (PAN)/kraft lignin-g-PAN copolymer blends electrospun nanofibers
- Chiral ionic liquids with a (−)-menthol component as wood preservatives
- Performance of waterborne copper/organic wood preservatives in an AWPA E14 soft-rot laboratory soil bed test using modified soil
- Erratum
- Erratum to: Water sorption hysteresis in wood: II mathematical modeling – functions beyond data fitting
Articles in the same Issue
- Frontmatter
- Original Articles
- Enzymatic grafting of kraft lignin as a wood bio-protection strategy. Part 1: factors affecting the process
- Enzymatic grafting of kraft lignin as a wood bio-protection strategy. Part 2: effectiveness against wood destroying basidiomycetes. Effect of copper entrapment
- Isolation and characterization of triterpenoids from the stem barks of Pinus massoniana
- Radial distribution of monomeric, dimeric and trimeric norlignans and their polymerization in Cryptomeria japonica heartwood
- Influence of length and sensor positioning on acoustic time-of-flight (ToF) measurement in structural timber
- Calcium phosphate bonded wood and fiber composite panels: production and optimization of panel properties
- Water sorption hysteresis in wood: III physical modeling by molecular simulation
- Characteristics of carbon nanofibers produced from lignin/polyacrylonitrile (PAN)/kraft lignin-g-PAN copolymer blends electrospun nanofibers
- Chiral ionic liquids with a (−)-menthol component as wood preservatives
- Performance of waterborne copper/organic wood preservatives in an AWPA E14 soft-rot laboratory soil bed test using modified soil
- Erratum
- Erratum to: Water sorption hysteresis in wood: II mathematical modeling – functions beyond data fitting