Modulus of elasticity of I-214 young poplar wood from standing trees to sawn timber: influence of the age and stand density

Abstract This study aimed to investigate the effects of juvenile spacing (precommercial thinning), thinning, and fertilization on Douglas-fir butt log (first 4.9 m) and second log (4.9–10 m) quality attributes: juvenile wood percentage, heartwood percentage, rings per inch, specific gravity, and modulus of elasticity. A 41-year-old, 36.6 m site index Douglas-fir stand in western Oregon, USA was selected as the first stand to explore. Nine common silviculture pathway treatments of juvenile spacing, thinning, and fertilization were applied to independent 0.404-hectare plots. Ninety-nine trees were felled and disks cut at five heights along the stem. Wood properties were measured and calculated from the disks for log quality attributes. There was no effect of silvicultural treatments on log heartwood percentage, but significant effects on other log quality attributes were observed. Juvenile wood percentage and rings per inch declined with stand density control and fertilization treatment. Responses to thinning and fertilization in log specific gravity depend on juvenile spacing. Also, thinning and juvenile spacing were shown to have impacts on log modulus of elasticity.

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Non-Destructive Measurement of the Modulus of Elasticity of Wood Using Acoustical Stress Waves

Arboriculture & Urban Forestry ◽

10.48044/jauf.2016.021 ◽

2016 ◽

Vol 42 (4) ◽

Author(s):

Gregory Dahle ◽

Aaron Carpenter ◽

David DeVallance

Keyword(s):

Stress Wave ◽

Modulus Of Elasticity ◽

Flexural Modulus ◽

Testing Machine ◽

Prediction Equation ◽

Biomechanical Models ◽

Standing Trees ◽

Acoustic Testing ◽

Destructive Measurement ◽

Non Destructive

Many biomechanical models include modulus of elasticity (E) but it is not always available in the literature. It would be useful to directly measure E for species, and one of the standard techniques for doing so is to utilize a universal testing machine (UTM). While laboratory testing can determine static flexural modulus of elasticity using a UTM, it requires destructive sampling and therefore is only useful after a tree or limb has been removed. Acoustic testing can be used to estimate the dynamic modulus of elasticity (DMOE) of wood, by measuring the speed of sound through a sample of wood without the need to remove any wood samples. This research investigated if acoustic testing can be used to accurately estimate the modulus of elasticity of green wood. Stump sprouts arising after a shelterwood harvest were cut and left at room temperature (21.1°C, warm) or conditioned to -6.7°C (frozen). The modulus of elasticity was measured using a stress-wave timer (DMOE) and a UTM (ES). The DMOE was higher in the frozen samples, but temperature did not affect ES. While the stress-wave timer used in the study found a slightly higher E than a UTM, a simple prediction equation was determined for converting the results. Researchers believe tools such as this can be successfully utilized by the arboriculture industry to rapidly assess the modulus of elasticity of standing trees in the field.

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Prediction of modulus of elasticity of poplar wood using ultrasonic technique by applying empirical correction factors

Measurement ◽

10.1016/j.measurement.2018.11.076 ◽

2019 ◽

Vol 135 ◽

pp. 392-399 ◽

Cited By ~ 7

Author(s):

Azin Ettelaei ◽

Mohammad Layeghi ◽

Hamid Zarea Hosseinabadi ◽

Ghanbar Ebrahimi

Keyword(s):

Modulus Of Elasticity ◽

Ultrasonic Technique ◽

Correction Factors ◽

Poplar Wood ◽

Empirical Correction

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Predicting the static modulus of elasticity in eastern cottonwood (Populus deltoides) using stress wave non-destructive testing in standing trees

European Journal of Wood and Wood Products ◽

10.1007/s00107-016-1043-0 ◽

2016 ◽

Vol 74 (6) ◽

pp. 885-892 ◽

Cited By ~ 1

Author(s):

Mehrab Madhoushi ◽

Soheyla Daneshvar

Keyword(s):

Stress Wave ◽

Modulus Of Elasticity ◽

Populus Deltoides ◽

Non Destructive Testing ◽

Destructive Testing ◽

Eastern Cottonwood ◽

Static Modulus ◽

Standing Trees ◽

Static Modulus Of Elasticity ◽

Non Destructive

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Applying Machine Strength Grading System to Round Timber Used in Hydraulic Engineering Works

Forests ◽

10.3390/f12030281 ◽

2021 ◽

Vol 12 (3) ◽

pp. 281

Author(s):

Michela Nocetti ◽

Giovanni Aminti ◽

C. Brand Wessels ◽

Michele Brunetti

Keyword(s):

Modulus Of Elasticity ◽

Dynamic Modulus ◽

Acoustic Velocity ◽

Hydraulic Engineering ◽

Raw Material ◽

Dynamic Modulus Of Elasticity ◽

Sawn Timber ◽

Mechanical Selection ◽

Round Timber ◽

Selection Of

Round timber is often used for hydraulic engineering works, but the strength grading of round logs is not as well developed as that of sawn timber. The advantages of using defined strength classes, as well as the proper selection of the raw material, could be applicable to hydraulic works as well. In this study, the methods and rules developed for sawn timber were applied to the mechanical selection of oak round logs, paying particular attention to the issue of the simplicity of grading operations and the moisture content of the timber. Both the acoustic velocity and dynamic modulus of elasticity of oak logs were measured with different instruments before performing destructive bending tests; machine settings were derived for both properties and dry and wet grading operations were simulated to compare efficiency. The use of the dynamic modulus of elasticity makes machine grading more efficient. On the other hand, the use of acoustic velocity alone is feasible and makes the procedure much faster, even if wet grading resulted in very conservative estimations. The yields obtained were similar for lower grades, but to achieve higher strength classes, the dynamic modulus was preferable. For very fast and less expensive measurements, velocity could be considered an appropriate method, as an improvement over the use of unselected material.

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Development of a model describing modulus of elasticity across environmental and stand density gradients in plantation-grown Pinus radiata within New Zealand

Canadian Journal of Forest Research ◽

10.1139/x10-103 ◽

2010 ◽

Vol 40 (8) ◽

pp. 1558-1566 ◽

Cited By ~ 17

Author(s):

Michael S. Watt ◽

Branislav Zoric

Keyword(s):

Pinus Radiata ◽

Modulus Of Elasticity ◽

Environmental Gradients ◽

Stand Density ◽

Radiata Pine ◽

Clonal Variation ◽

Simple Formulation ◽

Wide Range ◽

Level Model ◽

End Use

Modulus of elasticity (E) is an important property in plantation grown softwoods that describes resistance of timber to deformation under load and is a key criterion in machine stress grading. This paper presents an accurate (R2 = 0.96) site-level model of E for radiata pine ( Pinus radiata D. Don) that is applicable across a wide range of tree ages and broad environmental gradients and sensitive to a wide variation in stand density. In the final model, E increased sigmoidally with age and increased linearly with both stem slenderness (height/diameter at 1.4 m) and mean minimum autumn air temperature. For a given age, the model shows stem slenderness to be the main determinant of environmental variation in E, with variation in E ranging approximately 10 GPa across the range in slenderness. Given the simple formulation, this model could be readily used by managers to gain greater understanding of how they can manipulate stands to achieve desired end-use products and maximize crop value. Further research should extend the developed framework so that it can be used to account for intratree, intertree, and clonal variation in E.

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Quality and Bending Properties of Scots Pine (Pinus Sylvestris L.) Sawn Timber

Forests ◽

10.3390/f11111200 ◽

2020 ◽

Vol 11 (11) ◽

pp. 1200

Author(s):

Izabela Burawska-Kupniewska ◽

Sławomir Krzosek ◽

Piotr Mańkowski ◽

Marek Grześkiewicz

Keyword(s):

Mechanical Properties ◽

Scots Pine ◽

Modulus Of Elasticity ◽

Bending Strength ◽

Mechanical Parameters ◽

Bending Properties ◽

Characteristic Values ◽

Sawn Timber ◽

The Moment

The paper presents the partial research results of a mechanical properties study conducted on Scots pine from the Silesian Forestry Area in Poland. The scope of research included the visual strength grading of the timber according to the PN-D-94021:2013 standard, mechanical testing (according to EN 408:2012) and an attempt to assign visuals to the C strength classes. The EN 1912: 2012 standard assigns the visual sorting classes of individual wood species (according to national sorting standards) to the C strength classes introduced by the EN 338: 2018 standard. At the moment, this standard does not assign Polish visual sorting classes (KW, KS, and KG) to C strength classes. The obtained MOE (modulus of elasticity) and MOR (static bending strength) values were corrected according to the EN 384:2018 standard, and their characteristic values were later calculated. On this basis, we proposed a classification of the grading classes determined on the basis of PN-D-94021 into C classes described in EN 338:2018, which is necessary in the process of the transposition of Polish strength grades (KW, KS, KG, and Reject) and the qualification of them in line with EN 1912:2012. The calculated characteristic values of density, MOR and E0 (the modulus of elasticity parallel to the grain) allowed us to assign Polish visual grades KW, KS, and KG to C35, C30, and C20, respectively. The pine timber under research had high physical and mechanical parameters, which translated into high C classes to which the KW, KS, and KG timber categories were assigned.

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Influence of tree morphology, genetics, and initial stand density on outerwood modulus of elasticity of 17-year-old Pinus radiata

Forest Ecology and Management ◽

10.1016/j.foreco.2007.03.057 ◽

2007 ◽

Vol 244 (1-3) ◽

pp. 86-92 ◽

Cited By ~ 27

Author(s):

Matthew J. Waghorn ◽

Michael S. Watt ◽

Euan G. Mason

Keyword(s):

Pinus Radiata ◽

Modulus Of Elasticity ◽

Stand Density ◽

Tree Morphology

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Efficiency of Visual and Machine Strength Grading of Sawn Timber with Respect to Log Type

Forests ◽

10.3390/f12111467 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1467

Author(s):

Izabela Burawska-Kupniewska ◽

Sławomir Krzosek ◽

Piotr Mańkowski

Keyword(s):

Modulus Of Elasticity ◽

Bending Strength ◽

Strength Class ◽

Limited Extent ◽

Visual Method ◽

Medium Quality ◽

Sawn Timber ◽

Machine Strength

A batch of pine timber sawn from butt, middle and top logs was strength graded with the visual method (classification into grading classes KW—best quality, KS—medium quality, KG—inferior quality and Reject) and with the machine strength grading method—performed with the use of a mobile timber grader (classification into C strength classes). We compared the efficiency of grading classes and strength classes, depending on the type of log from which the material was obtained (butt, middle, top). Next, a strength grading machine was used to measure the modulus of elasticity in bending (MOE) and static bending strength (MOR). The ANOVA confirmed the influence of both the log type (butt, middle, top), the C strength class, and the visual strength grading class on the values of density (DEN) and MOR. Timber density and MOR decreased from the butt log section to the top log section. The ANOVA confirmed the influence of log type on MOE values, but only to a limited extent.

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