Predicting the longitudinal modulus of elasticity of Sitka spruce from cellulose orientation and abundance

Holzforschung ◽  
2010 ◽  
Vol 64 (4) ◽  
Author(s):  
J. Paul McLean ◽  
Robert Evans ◽  
John R. Moore
Keyword(s):  
Bulk Density ◽  
Modulus Of Elasticity ◽  
Microfibril Angle ◽  
Sitka Spruce ◽  
Picea Sitchensis ◽  
Model Parameters ◽  
Bending Tests ◽  
Wood Stiffness ◽  
Using Data ◽  
Longitudinal Modulus

Abstract Sitka spruce (Picea sitchensis) is the most widely planted commercial tree species in the United Kingdom and Ireland. Because of the increasing use of this species for construction, the ability to predict wood stiffness is becoming more important. In this paper, a number of models are developed using data on cellulose abundance and orientation obtained from the SilviScan-3 system to predict the longitudinal modulus of elasticity (MOE) of small defect-free specimens. Longitudinal MOE was obtained from both bending tests and a sonic resonance technique. Overall, stronger relationships were found between the various measures of cellulose abundance and orientation and the dynamic MOE obtained from the sonic resonance measurements, rather than with the static MOE obtained from bending tests. There was only a moderate relationship between wood bulk density and dynamic MOE (R2=0.423), but this relationship was improved when density was divided by microfibril angle (R2=0.760). The best model for predicting both static and dynamic MOE involved the product of bulk density and the coefficient of variation in the azimuthal intensity profile (R2=0.725 and 0.862, respectively). The model parameters obtained for Sitka spruce differed from those obtained in earlier studies on Pinus radiata and Eucalyptus delegatensis, indicating that the model might require recalibration before it can be applied to different species.

Evaluation of Longitudinal Modulus of Elasticity in Wood Species for Structural Application

2014 ◽  
Vol 1025-1026 ◽  
pp. 192-195
Author(s):  
Eduardo Chahud ◽  
Luiz Antônio Melgaço Nunes Branco ◽  
André Luis Christoforo ◽  
Francisco Antonio Rocco Lahr ◽  
Rosane Aparecida Gomes Battistelle ◽  
...  
Keyword(s):  
Wood Species ◽  
Modulus Of Elasticity ◽  
Mechanical Test ◽  
Font Size ◽  
Bending Tests ◽  
Structural Application ◽  
Longitudinal Elastic Modulus ◽  
Longitudinal Modulus ◽  
Dipteryx Odorata ◽  
Brazilian Standard

1024x768 This research aimed to investigate possible differences in values of longitudinal modulus of elasticity for wood species usually employed for structural purposes, as Castanheira (Bertholletia excelsa), Cambará (Erisma uncinatum), Cumaru (Dipteryx odorata), Jatobá (Hymenaea stilbocarpa), Garapa (Apuleia leiocarpa) and Peroba Rosa (Aspidosperma polyneuron), obtained from compression and tension parallel to grain, and static bending tests. Recommendations of the Brazilian standard ABNT NBR 7190:1997, Annex B, were followed. Statistical analysis results for the cited properties, had equivalent averages for the six wood species analyzed. This confirms that any of the three tests can be used to obtain the longitudinal elastic modulus and which could avoid the necessity of evaluating stiffness values for wood by more than one kind of mechanical test. Normal 0 21 false false false PT-BR X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

Genetic relationships between wood quality traits and diameter growth of juvenile core wood in Sitka spruce

2013 ◽  
Vol 43 (1) ◽  
pp. 1-6 ◽  
Author(s):  
S.G. Kennedy ◽  
A.D. Cameron ◽  
S.J. Lee
Keyword(s):  
Growth Rate ◽  
Genetic Correlation ◽  
Modulus Of Elasticity ◽  
Genetic Relationships ◽  
Wood Quality ◽  
Wood Properties ◽  
Sitka Spruce ◽  
Acoustic Velocity ◽  
Picea Sitchensis ◽  
Good Growth

The trend towards shorter rotations in planted conifer stands has resulted in a reduction in the proportion of mature wood relative to juvenile core wood, raising concerns that the mechanical performance of sawn battens will be affected. The potential to improve the wood quality of the juvenile core of Sitka spruce (Picea sitchensis (Bong.) Carrière) without compromising growth rate was investigated. Rapid and inexpensive indirect methods of assessing wood properties on standing trees using a Pilodyn gun and acoustic velocity were compared with direct measurements made on wood samples cut from the juvenile core. Strong genetic correlations were observed between Pilodyn gun values and direct measures of density (–0.76) and between the square of acoustic velocity and modulus of elasticity (0.73). The genetic correlation between the square of acoustic velocity and microfibril angle was also strong (–0.84). These results suggest that indirect assessments of wood properties within juvenile core wood are sufficiently reliable for these techniques to be used in the Sitka spruce breeding programme. Although a strong negative genetic correlation between diameter at breast height and density was noted (–0.79), sufficient variation exists within the breeding population to select families with both good growth rate and high modulus of elasticity wood.

Evaluating a Test Parameter in Static Bending for Pinus sp. Wood

2014 ◽  
Vol 1025-1026 ◽  
pp. 196-199
Author(s):  
Elen Aparecida Martines Morales ◽  
Helder Kenzo Kondo ◽  
Juliana Cortez Barbosa ◽  
Cristiane Inácio de Campos ◽  
Francisco Antonio Rocco Lahr ◽  
...  
Keyword(s):  
Shear Stress ◽  
Cross Section ◽  
Modulus Of Elasticity ◽  
Nonlinear Behavior ◽  
Pinus Elliottii ◽  
Vertical Deflection ◽  
Test Parameter ◽  
Bending Tests ◽  
Paulo State ◽  
Longitudinal Modulus

Abstract. The study aimed to analyze the longitudinal modulus of elasticity (Em), based on static bending tests, in different spans and confirm that it’s necessary adopt as 21 the ratio between span and height of the cross section of the specimen to turn no significant the influence of shear stress on vertical deflection. So, simplified equation to determine Emcan be employed. Specimens ofPinus elliottiivar.elliottiiandPinus elliottiivar. elliottii×Pinus cariabeaehondurensis(hybrid), came from Itapeva region, São Paulo State, Brazil, were considered. Bending tests were conducted in Labs of Experimental Campus Itapeva, UNESP, adapting recommendations of Brazilian Code ABNT NBR 7190. Twelve specimens of each species were tested. The trend lines for the plotted graphics showed clearly a nonlinear behavior until the neighborhood of ratio 21 and no expressive variations after this point, confirming that normative recommendations are correct.

Variation of Microfibril Angle Between Four Provenances of Sitka Spruce (Picea sitchensis [Bong.] Carr.)

Plant Biology ◽  
2002 ◽  
Vol 4 (1) ◽  
pp. 27-33 ◽  
Author(s):  
U. Vainio ◽  
S. Andersson ◽  
R. Serimaa ◽  
T. Paakkari ◽  
P. Saranpää ◽  
...  
Keyword(s):  
Microfibril Angle ◽  
Sitka Spruce ◽  
Picea Sitchensis

Earlywood and latewood elastic properties in loblolly pine

Holzforschung ◽  
2005 ◽  
Vol 59 (5) ◽  
pp. 531-538 ◽  
Author(s):  
Steven Cramer ◽  
David Kretschmann ◽  
Roderic Lakes ◽  
Troy Schmidt
Keyword(s):  
Specific Gravity ◽  
Shear Modulus ◽  
Elastic Properties ◽  
Loblolly Pine ◽  
Modulus Of Elasticity ◽  
Compression Wood ◽  
Microfibril Angle ◽  
Testing Procedures ◽  
Pine Trees ◽  
Longitudinal Modulus

Abstract The elastic properties of earlywood and latewood and their variability were measured in 388 specimens from six loblolly pine trees in a commercial plantation. Properties measured included longitudinal modulus of elasticity, shear modulus, specific gravity, microfibril angle and presence of compression wood. Novel testing procedures were developed to measure properties from specimens of 1 mm×1 mm×30 mm from earlywood or latewood. The elastic properties varied substantially circumferentially around a given ring and this variation was nearly as large as the variation across rings. The elastic properties varied by ring and height, but while the modulus of elasticity increased with height, the shear modulus decreased with height. A strong correlation was found between modulus of elasticity and shear modulus, but only at low heights and inner rings. Specific gravity and microfibril angle were the strongest predictors of elastic properties and explained 75% of the variation in modulus of elasticity for latewood. Despite being the best predictors in this study, these parameters accounted for less than half of the variability of earlywood modulus of elasticity, earlywood shear modulus and latewood shear modulus.

Influence of selective breeding on the development of juvenile wood in Sitka spruce

2005 ◽  
Vol 35 (12) ◽  
pp. 2951-2960 ◽  
Author(s):  
A D Cameron ◽  
S J Lee ◽  
A K Livingston ◽  
J A Petty
Keyword(s):  
Growth Rate ◽  
Selective Breeding ◽  
Juvenile Wood ◽  
Microfibril Angle ◽  
Ring Width ◽  
High Growth ◽  
Sitka Spruce ◽  
Picea Sitchensis ◽  
Fast Growing ◽  
Slow Growing

The effect of selective breeding on juvenile wood formation in 24-year-old Sitka spruce (Picea sitchensis (Bong.) Carr.) was investigated. Properties associated with juvenile wood in fast-growing progenies were compared with those from slow-growing progenies and an unimproved control of similar growth rate (origin Queen Charlotte Islands, British Columbia, Canada). Large differences in properties associated with juvenile wood, namely high annual ring width, high microfibril angle, low density, and low latewood proportion, were observed in the first 12 or so rings from the pith between treatments. These properties were significantly inferior in the fast-growing progenies in comparison with the slow-growing treatments. From the 13th ring outwards, no significant differences were found between treatments in all attributes measured. Coefficients of determination (R2) between ring width and wood properties measured from rings 1 to 12 revealed only weak associations. Conversely, R2 values calculated for rings 13–19 revealed significant associations, indicating that density, latewood proportion, and tracheid length and diameter declined, while microfibril angle increased, with increasing ring width. The period of formation and the properties of juvenile wood appear to be largely independent of growth rate. High growth rate in the mature wood remains a concern in terms of wood quality.

scholarly journals Shear and longitudinal modulus of elasticity in wood: relations based on static bending tests

2017 ◽  
Vol 39 (4) ◽  
pp. 433 ◽  
Author(s):  
Francisco Antonio Rocco Lahr ◽  
André Luis Christoforo ◽  
Luciano Donizeti Varanda ◽  
Eduardo Chahud ◽  
Victor Almeida De Araújo ◽  
...  
Keyword(s):  
Modulus Of Elasticity ◽  
Bending Tests ◽  
Longitudinal Modulus

APPLICATION OF NEAR INFRARED SPECTROSCOPY TO A DIVERSE RANGE OF SPECIES DEMONSTRATING WIDE DENSITY AND STIFFNESS VARIATION

IAWA Journal ◽  
2001 ◽  
Vol 22 (4) ◽  
pp. 415-429 ◽  
Author(s):  
Laurence Schimleck ◽  
Robert Evans ◽  
Jugo Ilic
Keyword(s):  
Physical Properties ◽  
Modulus Of Elasticity ◽  
Near Infrared ◽  
Microfibril Angle ◽  
Nir Spectroscopy ◽  
Wood Properties ◽  
Mixed Species ◽  
Diverse Range ◽  
Wide Range ◽  
Longitudinal Modulus

The application of near infrared (NIR) spectroscopy to a large number of mixed species that display extremely wide variations in wood chemistry, anatomy and physical properties, is described. The mixed species samples were characterized in terms of density, longitudinal modulus of elasticity and microfibril angle. NIR spectra were obtained from the radial / longitudinal face of each sample and used to generate calibrations for the measured physical properties. The calibrations developed for density and longitudinal modulus of elasticity had the highest coefficients of determination (R2) and demonstrated that it is possible to develop general calibrations for these important wood properties across a wide range of species.The mixed species calibrations were used to estimate wood properties of two species, Eucalyptus delegatensis R.T. Baker and Pinus radiata D.Don. The results obtained for density and longitudinal modulus of elasticity indicated that mixed species calibrations can be used to rank trees. In practice the extreme variation of samples selected for this study would not be required. It is expected that refinement of calibrations, through sample selection, would provide more accurate prediction of physical properties.

scholarly journals Non-Destructive Assessment of Wood Stiffness in Scots Pine (Pinus sylvestris L.) and its Use in Forest Tree Improvement

Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 491 ◽  
Author(s):  
Irena Fundova ◽  
Tomas Funda ◽  
Harry X. Wu
Keyword(s):  
Scots Pine ◽  
Growth Traits ◽  
Wood Quality ◽  
Genetic Correlations ◽  
Forest Tree ◽  
Wood Stiffness ◽  
Standing Trees ◽  
Genetic And Phenotypic Correlations ◽  
Sib Families ◽  
Using Data

Wood stiffness is an important wood mechanical property that predetermines the suitability of sawn timber for construction purposes. Negative genetic correlations between wood stiffness and growth traits have, however, been reported for many conifer species including Scots pine. It is, therefore, important that breeding programs consider wood stiffness and growth traits simultaneously. The study aims to (1) evaluate different approaches of calculating the dynamic modulus of elasticity (MOE, non-destructively assessed stiffness) using data from X-ray analysis (SilviScan) as a benchmark, (2) estimate genetic parameters, and (3) apply index selection. In total, we non-destructively measured 622 standing trees from 175 full-sib families for acoustic velocity (VEL) using Hitman and for wood density (DEN) using Resistograph and Pilodyn. We combined VEL with different wood densities, raw (DENRES) and adjusted (DENRES.TB) Resistograph density, Pilodyn density measured with (DENPIL) and without bark (DENPIL.B), constant of 1000 kg·m−3 (DENCONST), and SilviScan density (DENSILV), to calculate MOEs and compare them with the benchmark SilviScan MOE (MOESILV). We also derived Smith–Hazel indices for simultaneous improvement of stem diameter (DBH) and wood stiffness. The highest additive genetic and phenotypic correlations of the benchmark MOESILV with the alternative MOE measures (tested) were attained by MOEDENSILV (0.95 and 0.75, respectively) and were closely followed by MOEDENRES.TB (0.91 and 0.70, respectively) and MOEDENCONST and VEL (0.91 and 0.65, respectively for both). Correlations with MOEDENPIL, MOEDENPIL.B, and MOEDENRES were lower. Narrow-sense heritabilities were moderate, ranging from 0.39 (MOESILV) to 0.46 (MOEDENSILV). All indices revealed an opportunity for joint improvement of DBH and MOE. Conclusions: MOEDENRES.TB appears to be the most efficient approach for indirect selection for wood stiffness in Scots pine, although VEL alone and MOEDENCONST have provided very good results too. An index combining DBH and MOEDENRES.TB seems to offer the best compromise for simultaneous improvement of growth, fiber, and wood quality traits.

Mechanical Behavior for some Cobalt Alloys

2015 ◽  
Vol 1114 ◽  
pp. 9-12
Author(s):  
Alexandru Ghiban ◽  
Brandusa Ghiban ◽  
Cristina Maria Borţun ◽  
Nicolae Serban ◽  
Mihai Buzatu
Keyword(s):  
Tensile Strength ◽  
Chemical Composition ◽  
Mechanical Behavior ◽  
Mechanical Characteristics ◽  
Fractographic Analysis ◽  
Cobalt Alloys ◽  
Dental Alloys ◽  
Bending Tests ◽  
Longitudinal Modulus

Four compositions of some usually commercial dental alloys were investigated in order to determine the mechanical characteristics and fractographic analysis of tensile and bending tests surfaces. A correlation between chemical composition (either molybdenum or molybdenum and chromium contents) and mechanical characteristics (longitudinal modulus, tensile strength and elongation) were finally done.

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