Comparison of Non-Destructive Methods Based on Natural Frequency for Determining the Modulus of Elasticity of Cupressus lusitanica and Populus x canadensis

Hodoušek, Matěj; Dias, Alfredo M. P. G.; Martins, Carlos; Marques, André Filipe Silva; Böhm, Martin

doi:10.15376/biores.12.1.270-282

Cited by 17 publications

(28 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Non-destructive tools were used to predict those properties through simple linear correlation analyses. The Longitudinal Vibration Method (LVM), which consists Forests 2020, 11, 418 3 of 12 of the measurement of the material's natural frequency, was used, since it was previously validated for other species, like Maritime pine [27], Poplar [28] and Blue gum [29]. The present paper intends to improve the knowledge of the Portuguese Blackwood for structural applications, highlighting the species' potential to produce glulam as a way to add value to the raw material obtained from the proliferation of the species.…”

Section: Introductionmentioning

confidence: 99%

Assessment of Bending Properties of Sawn and Glulam Blackwood in Portugal

Martins

Monteiro

Knapic

et al. 2020

Forests

Self Cite

View full text Add to dashboard Cite

Portuguese forests have changed in recent years. These changes were mainly boosted by the wildfires that affected a significant percentage of the softwood area. Data from 2015, conveyed by the Portuguese Institute for Nature Conservation and Forests, indicates that hardwoods occupy 70% of the Portuguese forest area. This paper presents the Blackwood (Acacia melanoxylon R. Br.) species potential, focusing on construction applications, based on recent studies performed at the University of Coimbra and SerQ-Forest Innovation and Competences Center. The valuation of Blackwood for structural applications has been considered through the non-destructive and destructive assessment of their mechanical properties as sawn wood. Their potential was also assessed for a more technologically engineered wood product, the glulam. The dynamic modulus of elasticity (MOE) was estimated through the Longitudinal Vibration Method (LVM) and the Transformed Section Method (TSM); the static MOE and bending strength were assessed through a four-point bending test. Agreement was obtained between both approaches. Sawn Portuguese Blackwood showed a density of 647 kg/m 3 , 13,900 MPa of MOE and a bending strength of 65 MPa (mean values). The glulam beams fabricated with this raw material had improved properties relative to sawn wood, most obviously concerning the bending strength, with an improvement of 29%. This proves the significant ability and potential of these species to be used in construction products with structural purposes like sawn wood and glulam.

show abstract

Section: Introductionmentioning

confidence: 99%

Assessment of Bending Properties of Sawn and Glulam Blackwood in Portugal

Martins

Monteiro

Knapic

et al. 2020

Forests

Self Cite

View full text Add to dashboard Cite

show abstract

“…Wood is a versatile material with advantages over other materials, such as concrete, steel, aluminum, and plastic. Among these advantages are the strong relationship between the mechanical strength and density, low energy consumption during production, its status as a renewable resource, and good thermal and electrical insulation (Kollmann and Côté 1968;Vidal et al 2015;Hodoušek et al 2017;Osuji and Nwankwo 2017;de Almeida et al 2018). However, wood is composed of a relatively hydrophobic matrix and hydrophilic fibers, which makes its use less disseminated because of its susceptibility to wood-deteriorating organisms (Mohan et al 2008;Temiz et al 2010;2013;Ferrarini et al 2012).…”

Section: Introductionmentioning

confidence: 99%

Influence of CCA-A preservative on physical-mechanical properties of Brazilian tropical woods

Almeida

Criscuolo

Almeida

et al. 2019

BioRes

View full text Add to dashboard Cite

Fast-growing species are gradually being used more in the Brazilian timber market. Such species are more susceptible to deterioration and require conservative treatment to prolong their service life. This work analyzed the influence of the chromated copper arsenate oxide (CCA-A) treatment on the physical-mechanical properties of the tropical woods Simarouba amara (C20), Cedrelinga catenaeformis (C30), and Erisma uncinatum (C40), which were chosen to cover the three lower strength classes, as prescribed by Brazilian Standard Norm. The CCA-A was applied to the wood with the vacuum-pressure process, which could increase the amount of surface defects and weaken the wood properties. To investigate the influence of this process, complete characterization of the species with and without CCA-A was performed, and a Tukey’s multiple comparisons test (5% significance level) was applied. Also, scanning electron microscopy (SEM) images and energy dispersive spectra (EDS) were obtained to investigate the behavior of the preservative at the cellular level. Through the obtained results, it was concluded that the CCA did not affect the physical-mechanical properties of the studied species.

show abstract

“…The present research focuses on the use of Blue gum and its combination with Poplar (both grown in Portuguese forest) for glued laminated timber. The use of non-destructive methods (longitudinal vibration method and transformed section method) was considered for the prediction of static bending properties, since previous studies have demonstrated high accuracy of both methods (Hodousek et al 2017 andMartins et al 2018). A total of 7 glulam beams were produced in laboratory, non-destructively tested through longitudinal vibration method and destructively tested following EN 408 requirements (CEN 2012).…”

Section: Introductionmentioning

confidence: 99%

Use of northern hardwoods in glued-laminated timber: a study of bondline shear strength and resistance to moisture

et al. 2020

View full text Add to dashboard Cite

The growing demand for engineered wood products in the construction sector has resulted in the diversification of the product offer. Used marginally in structural products in North America, northern hardwoods are now attracting a growing interest from industry and policy makers because of their outstanding strength as well as their high availability and distinctive appearance. Currently, there is no standard in Canada governing the use of hardwoods in the manufacturing of glued-laminated timber. As part of a larger project aiming to assemble the basic knowledge that would lead to such standard, the specific objective of this study was to assess the shear strength in dry and wet conditions of assemblies made from different hardwood species and structural adhesives. Results suggest that a mean shear strength as high as 20.5 MPa for white oak, 18.8 MPa for white ash and respectively 18.2 MPa and 17.4 MPa for yellow birch and paper birch can be obtained in dry conditions. The choice of adhesive did not affect the dry shear strength of our specimens, but differences were observed in wet conditions. Specimens bonded with melamine-formaldehyde adhesive had generally the highest wet shear strength and wood failure values. Our results also highlight the important influence of wood density on the percentage of failure that occurs in wood and, to a lesser extent, on shear strength. Further investigations on finger joint strength and full-size bending tests will allow confirming the potential for the investigated species to be used in glued-laminated timber.

show abstract

Comparison of Non-Destructive Methods Based on Natural Frequency for Determining the Modulus of Elasticity of Cupressus lusitanica and Populus x canadensis

Cited by 17 publications

References 20 publications

Assessment of Bending Properties of Sawn and Glulam Blackwood in Portugal

Assessment of Bending Properties of Sawn and Glulam Blackwood in Portugal

Influence of CCA-A preservative on physical-mechanical properties of Brazilian tropical woods

Use of northern hardwoods in glued-laminated timber: a study of bondline shear strength and resistance to moisture

Contact Info

Product

Resources

About