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Outputs (192)

Thinking beyond the usual strength grades – with examples of British spruce and larch
Presentation / Conference Contribution
Ridley-Ellis, D., Adams, S., & Lehneke, S. (2016, August). Thinking beyond the usual strength grades – with examples of British spruce and larch. Presented at World Conference on Timber Engineering (WCTE 2016)

This paper summarises the processes and normative requirements involved in grading of structural timber, and outlines a number of areas in which matters may be improved, so as to make better use of the true properties of the timber resource used. The... Read More about Thinking beyond the usual strength grades – with examples of British spruce and larch.

The daily cycle of moisture content expansion and contraction in UK-grown Sitka spruce trees
Presentation / Conference Contribution
Adams, S., & Ridley-Ellis, D. (2018, June). The daily cycle of moisture content expansion and contraction in UK-grown Sitka spruce trees. Paper presented at Timber 2018

The diameter of five dominant Sitka spruce (Picea sitchensis) trees at Griffin Forest (near Aberfeldy, Scotland) were monitored at two minute intervals with dendrometers between April 2008 and October 2012. This experiment was designed to investigate... Read More about The daily cycle of moisture content expansion and contraction in UK-grown Sitka spruce trees.

Some thresholds for grading British grown spruce to optimised strength classes using longitudinal resonance
Presentation / Conference Contribution
Ridley-Ellis, D., Adams, S., & Lehneke, S. (2018, August). Some thresholds for grading British grown spruce to optimised strength classes using longitudinal resonance. Presented at World Conference on Timber Engineering, Seoul, Republic of Korea

The main commercial species in the UK and Ireland is Sitka spruce (Picea sitchensis), which is graded in combination with a small amount of Norway spruce (P. abies). It is typically graded to the European strength class C16, but actually has superior... Read More about Some thresholds for grading British grown spruce to optimised strength classes using longitudinal resonance.

Grading of British spruce cladding battens by ring width for density, fastener performance and fire
Presentation / Conference Contribution
Ridley-Ellis, D. (2019, October). Grading of British spruce cladding battens by ring width for density, fastener performance and fire. Presented at 15th Annual Meeting of the Northern European Network for Wood Science and Engineering, Lund, Sweden

The UK has a British Standard for external timber cladding, BS8605-1, in which support battens are defined as timber components of a section, grade, and durability, suitable for supporting external timber cladding. The term includes both battens (whi... Read More about Grading of British spruce cladding battens by ring width for density, fastener performance and fire.

The use of a visual grading code of practice in the UK in the assessment of the mechanical properties of in situ structural timber elements
Presentation / Conference Contribution
Bather, M. J., & Ridley-Ellis, D. J. (2019, September). The use of a visual grading code of practice in the UK in the assessment of the mechanical properties of in situ structural timber elements. Presented at 5th International Conference on Structural Health Assessment of Timber Structures (SHATiS), Guimarães, Portugal

The estimation of the mechanical properties of in situ timber elements is an essential part of the structural appraisal of many existing buildings and structures. Currently, in the UK, this appraisal
of load-bearing timber is generally carried out b... Read More about The use of a visual grading code of practice in the UK in the assessment of the mechanical properties of in situ structural timber elements.

Use of Nondestructive Techniques for Determination of Tension Parallel-to-Grain Properties of Spruce
Presentation / Conference Contribution
Gil-Moreno, D., O'Ceallaigh, C., Ridley-Ellis, D., & Harte, A. M. (2019, September). Use of Nondestructive Techniques for Determination of Tension Parallel-to-Grain Properties of Spruce. Presented at 21st International Nondestructive Testing and Evaluation of Wood Symposium, Freiburg, Germany

The paper presents a study of the tension properties of Irish-grown Sitka spruce. Fifty timber pieces were destructively tested having resonant frequency and knots measured. The aim was to improve knowledge of the performance of spruce in tension and... Read More about Use of Nondestructive Techniques for Determination of Tension Parallel-to-Grain Properties of Spruce.

Influence of knot area indexes on tension strength of Sitka spruce
Presentation / Conference Contribution
Gil-Moreno, D., Ridley-Ellis, D., & Harte, A. M. (2019, September). Influence of knot area indexes on tension strength of Sitka spruce. Presented at 15th Annual Meeting of the Northern European Network for Wood Science and Engineering, Lund, Sweden

It is well known that knots can reduce the strength of timber, and the selection of “critical section” for testing to EN 408 and EN 384 is typically based on the size and position of knots. In Ireland, the visual strength grading Standard IS 127 spec... Read More about Influence of knot area indexes on tension strength of Sitka spruce.

Quantification of chemical changes taking place in spruce wood structure following long period thermal treatment
Presentation / Conference Contribution
Popescu, C., Ridley-Ellis, D., & Popescu, M. (2019, August). Quantification of chemical changes taking place in spruce wood structure following long period thermal treatment. Paper presented at 2DCOS-10, The 10th International Symposium on Two-dimensional Correlation Spectroscopy, Changchun, China

Wood is a natural composite polymer containing different amounts of cellulose, lignin and hemicelluloses and some other low molecular compounds (i.e. extractives). Due to its structure wood is susceptible to degradation in the surrounding environment... Read More about Quantification of chemical changes taking place in spruce wood structure following long period thermal treatment.

Some awkward questions about density
Presentation / Conference Contribution
Ridley-Ellis, D., & Cramer, M. (2020, September). Some awkward questions about density. Presented at Timber 2020, Online

There are several different concepts of wood density, such as specific gravity, basic density, dry density, and oven dry density. These are often confusing, and sometimes poorly described in the literature, but they can be unambiguously defined and m... Read More about Some awkward questions about density.

A brief look at alternative species in the UK
Presentation / Conference Contribution
Adams, S. H., & Ridley-Ellis, D. J. (2020, December). A brief look at alternative species in the UK. Presented at Northern European Network for Wood Science and Engineering – WSE2020, Online (Helsinki)