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Considerations for grading species combinations. The example of Douglas fir with larch in Ireland and UK (2023)
Conference Proceeding
Gil-Moreno, D., Ridley-Ellis, D., & Harte, A. M. (2023). Considerations for grading species combinations. The example of Douglas fir with larch in Ireland and UK. In A. Q. Nyrud, K. A. Malo, & K. Nore (Eds.), Proceedings from the 13th World Conference on Timber Engineering (2023) (773-779). https://doi.org/10.52202/069179-0106

This paper examines the grading of Douglas fir (Pseudotsuga menziesii) and larch (Larix spp.) as a strength grading species combination for the growth area formed by Ireland and the UK. The two genera produce higher timber quality than Sitka spruce (... Read More about Considerations for grading species combinations. The example of Douglas fir with larch in Ireland and UK.

Non-parametric lower confidence bounds for the fifth percentile - EN 14358 in comparison to a fully non-parametric approach (2023)
Conference Proceeding
Weidenhiller, A., Ridley-Ellis, D., & Neumüller, A. (2023). Non-parametric lower confidence bounds for the fifth percentile - EN 14358 in comparison to a fully non-parametric approach. In A. Q. Nyrud, K. A. Malo, & K. Nore (Eds.), Proceedings from the 13th World Conference on Timber Engineering (2023) (735-739). https://doi.org/10.52202/069179-0101

In Europe, fifth percentile values are required for the calculation of characteristic values of strength and density. The European standard EN 14358:2016 defined three ways to calculate a 75% lower confidence bound (LCB) for such fifth percentile val... Read More about Non-parametric lower confidence bounds for the fifth percentile - EN 14358 in comparison to a fully non-parametric approach.

Considerations for grading species combinations. General remarks on scenarios and requirements (2023)
Conference Proceeding
Ridley-Ellis, D., Gil-Moreno, D., & Harte, A. M. (2023). Considerations for grading species combinations. General remarks on scenarios and requirements. In A. Q. Nyrud, K. A. Malo, & K. Nore (Eds.), Proceedings from the 13th World Conference on Timber Engineering (2023) (780-786). https://doi.org/10.52202/069179-0107

This paper discusses the situations in which timber species might be combined in commercial combinations, and the considerations relating to strength grading work. It is expected that more species combinations will be developed in the years to come,... Read More about Considerations for grading species combinations. General remarks on scenarios and requirements.

Test Machine Effect in the determination of modulus of elasticity for strength-graded timber (2021)
Conference Proceeding
Gil-Moreno, D., Ridley-Ellis, D., & Harte, A. M. (2021). Test Machine Effect in the determination of modulus of elasticity for strength-graded timber. In WCTE 2021: World Conference on Timber Engineering Proceedings

This paper investigates if the relationship between the global and local moduli of elasticity (MoE), measured in bending tests, is affected by the test machines employed, and how that may influence strength grading. The ultimate aim is to study the p... Read More about Test Machine Effect in the determination of modulus of elasticity for strength-graded timber.

Perception and use of timber in construction: A case study of Ireland and the UK (2021)
Conference Proceeding
O'Ceallaigh, C., Gil-Moreno, D., Ridley-Ellis, D., & Harte, A. M. (2021). Perception and use of timber in construction: A case study of Ireland and the UK. In WCTE 2021: World Conference on Timber Engineering Proceedings

A survey was carried out to examine the perception of timber in construction among industry stakeholders within northwest Europe. The survey received responses from 17 countries in total. The total results of all respondents are presented along with... Read More about Perception and use of timber in construction: A case study of Ireland and the UK.

A brief look at alternative species in the UK (2021)
Conference Proceeding
Adams, S. H., & Ridley-Ellis, D. J. (2021). A brief look at alternative species in the UK. In Proceedings of the 16th Annual Meeting of the Northern European Network for Wood Science and Engineering – WSE2020 (68-70)

A case study of timber demolition recycling in the UK (2021)
Conference Proceeding
Cramer, M., & Ridley-Ellis, D. (2021). A case study of timber demolition recycling in the UK. In Proceedings of the 16th Annual Meeting of the Northern European Network for Wood Science and Engineering – WSE2020 (89-91)

Some awkward questions about density (2020)
Conference Proceeding
Ridley-Ellis, D., & Cramer, M. (2020). Some awkward questions about density. In Timber 2020 Conference Proceedings (99-110)

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.

Influence of knot area indexes on tension strength of Sitka spruce (2019)
Conference Proceeding
Gil-Moreno, D., Ridley-Ellis, D., & Harte, A. M. (2019). Influence of knot area indexes on tension strength of Sitka spruce. In Proceedings of the 15th Annual Meeting of the Northern European Network for Wood Science and Engineering

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.

Grading of British spruce cladding battens by ring width for density, fastener performance and fire (2019)
Conference Proceeding
Ridley-Ellis, D. (2019). Grading of British spruce cladding battens by ring width for density, fastener performance and fire. In Proceedings of the 15th Annual Meeting of the Northern European Network for Wood Science and Engineering

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 (2019)
Conference Proceeding
Bather, M. J., & Ridley-Ellis, D. J. (2019). 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. In SHATiS 2019: 5th International Conference on Structural Health Assessment of Timber Structures (89-98)

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 (2019)
Conference Proceeding
Gil-Moreno, D., O'Ceallaigh, C., Ridley-Ellis, D., & Harte, A. M. (2019). Use of Nondestructive Techniques for Determination of Tension Parallel-to-Grain Properties of Spruce. In Proceedings: 21st International Nondestructive Testing and Evaluation of Wood Symposium, Freiburg, Germany 2019 (233-240)

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.

Some thresholds for grading British grown spruce to optimised strength classes using longitudinal resonance (2018)
Conference Proceeding
Ridley-Ellis, D., Adams, S., & Lehneke, S. (2018). Some thresholds for grading British grown spruce to optimised strength classes using longitudinal resonance.

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.

Using the right Modulus of Elasticity to get the best grades out of softwood timber species in Great Britain (2016)
Conference Proceeding
Gil-Moreno, D., Ridley-Ellis, D., & McLean, P. (2016). Using the right Modulus of Elasticity to get the best grades out of softwood timber species in Great Britain. In WCTE 2016 World Conference on Timber Engineering e-book Full Papers

The correct characterisation of modulus of elasticity in bending is fundamental for timber grading, especially when that property limits the allocation to a strength class. The aim of this paper is to empirically determine the relationship between EN... Read More about Using the right Modulus of Elasticity to get the best grades out of softwood timber species in Great Britain.

Thinking beyond the usual strength grades – with examples of British spruce and larch (2016)
Conference Proceeding
Ridley-Ellis, D., Adams, S., & Lehneke, S. (2016). Thinking beyond the usual strength grades – with examples of British spruce and larch. In Proceedings of the World Conference on Timber Engineering (WCTE 2016), August 22-25, 2016, Vienna, Austria, Eds.: J. Eberhardsteiner, W. Winter, A. Fadai, M. Pöll, Publisher: Vienna University of Technology

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.

Analysis of acoustical properties of wood and mode identification by sample scanning in the very near field (2016)
Conference Proceeding
Pantelić, F., Šumarac Pavlović, D., Mijić, M., & Ridley-Ellis, D. (2016). Analysis of acoustical properties of wood and mode identification by sample scanning in the very near field. In Zbornik apstrakata i program 60.konferencije ETRAN, Zlatibor

It is possible to achieve a good visualization of vibration modes by microphone scanning of a vibration excited sample of wood in very near field. The experimental settings, shown in this paper, were used for wood properties characterization and obse... Read More about Analysis of acoustical properties of wood and mode identification by sample scanning in the very near field.

Computational issues regarding lattice models for wood (2010)
Conference Proceeding
Reichert, T., & Ridley-Ellis, D. (2010). Computational issues regarding lattice models for wood. In A. Ceccotti (Ed.), 11th World Conference on Timber Engineering 2010 (WCTE 2010) (2127-2132)

This paper describes means to overcome some of the computational issues related to lattice models. The first is the use of a solution technique, different from a Newton-Raphson approach, called the Step-Size-Control (SSC) algorithm to handle strain-s... Read More about Computational issues regarding lattice models for wood.

Determining the Shear Modulus of Sitka Spruce from Torsion Tests (2008)
Conference Proceeding
Khokhar, A., Zhang, H., Ridley-Ellis, D., & Moore, J. (2008). Determining the Shear Modulus of Sitka Spruce from Torsion Tests. In 10th World Conference on Timber Engineering 2008 (2137-2144)

This paper presents details of the experimental method, and preliminary results from, a series of torsion tests undertaken to evaluate the shear modulus of Sitka spruce (Picea sitchensis) timber. Direct torsion tests were used to determine the variat... Read More about Determining the Shear Modulus of Sitka Spruce from Torsion Tests.

Torsion tests on small and large-scale RHS with circular wall cut-outs (2007)
Conference Proceeding
Ridley-Ellis, D., Owen, J. S., & Davies, G. (2007). Torsion tests on small and large-scale RHS with circular wall cut-outs.

The results of small and large-scale torsion tests on rectangular section tubes with circular wall perforations are presented and discussed. Perforations are shown to cause the torsional resistance to be re-duced by up to 60% and stiffness to be redu... Read More about Torsion tests on small and large-scale RHS with circular wall cut-outs.