Modulus of elasticity in three- and four-point bending of wood

Babiak, Marián; Gaff, Milan; Síkora, Adam; Hýsek, Štěpán

doi:10.1016/j.compstruct.2018.07.113

Cited by 44 publications

(22 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Five specimens were tested for each sample. The modulus of rupture (MOR) and modulus of elasticity (MOE) were calculated according to the following equations:

where P is the maximum load (N), determined experimentally from the curves, L is the length of the span (mm), which was set at 140 mm [ 36 ], b, is the width of the specimen (mm), d is the thickness of the specimen (mm), P 1 is the load at the proportional limit (N), and y 1 is the center deflection (mm) at the proportional limit load, which was set at approximately 40% of the maximum load [ 37 , 38 ].…”

Section: Methodsmentioning

confidence: 99%

“…where P is the maximum load (N), determined experimentally from the curves, L is the length of the span (mm), which was set at 140 mm [36], b, is the width of the specimen (mm), d is the thickness of the specimen (mm), P 1 is the load at the proportional limit (N), and y 1 is the center deflection (mm) at the proportional limit load, which was set at approximately 40% of the maximum load [37,38]. Scheme showing the wood specimens dimensions, and assembly positions for three-point bending test measurements (adapted from [37]).…”

Section: Equipmentmentioning

confidence: 99%

See 1 more Smart Citation

Consolidation of Fir Wood by Poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) Treatment: Study of Surface and Mechanical Characteristics

2020

View full text Add to dashboard Cite

The ability of poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) (PVBVA) to consolidate Fir wood was studied in terms of the surface and mechanical properties’ changes. Two variables were considered to treat the wood: (i) the concentration (5 and 10 wt.%) of PVBVA solutions and (ii) the method of application (brushing and immersion). The presence of PVBVA on the wood surfaces was confirmed by infrared spectroscopy. Surface roughness measured by optical profilometry did not reveal changes in the topography of the samples, and appropriate visual appearance was confirmed. Contact angle measurements showed that a droplet of the 10%-PVBVA solution needed ~50 s to reach the same contact angle decreasing rate as that measured for the 5%-PVBVA solution, suggesting there was some kind of induction time till the spreading process was no longer controlled by the viscosity, but by the solution-wood interactions. Water contact angle (WCA) measurements proved a more hydrophobic surface of the PVBVA-treated samples, compared to untreated wood. Mechanical characterization of the samples was done macroscopically by a three-point bending test and locally by the Shore D and Martens hardness (MH). Only results from MH experiments provided comparative results, indicating that treatment with PVBVA solutions increased wood hardness locally, being enhanced with solution concentration. The best surface mechanical properties were obtained for the samples immersed in the 10%-PVBVA solution.

show abstract

“…Five specimens were tested for each sample. The modulus of rupture (MOR) and modulus of elasticity (MOE) were calculated according to the following equations:

Section: Methodsmentioning

confidence: 99%

Section: Equipmentmentioning

confidence: 99%

Consolidation of Fir Wood by Poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) Treatment: Study of Surface and Mechanical Characteristics

2020

View full text Add to dashboard Cite

show abstract

“…S3C). The LW tracheids of the tensile parts outermost were subjected to longitudinal tension and LR shear coupling stresses, but the LW tracheids of the neutral layer bore only the LR shear stress [22]. The fracture morphologies of the LW tracheids cross section for the outermost tensile parts and the neutral layer are provided in Fig.…”

Section: Three-point Bending Fracturementioning

confidence: 99%

The fracture mechanism of softwood via hierarchical modelling analysis

Wang

Lin

et al. 2019

J Wood Sci

View full text Add to dashboard Cite

A hierarchical model of softwood was developed to effectively analyze stress concentration and predict initial fracture of the wood cell wall under different loading scenarios. The results indicated that the simulated stress concentration regions of the tracheid wall approximately matched the experimental initial fracture locations. The stress concentration and initial fracture of the tracheid wall under longitudinal tensile stress occurred in the S 2 layer. In the cases of pure longitudinal-radial (LR) or longitudinal-tangential (LT) in-plane shear loading, the highest stresses are observed in the S 1 /S 2 interface and the S 3 layer, but the initial fractures of the tracheids of the neutral layer under the LR or LT shear stress only occurred in the S 1 /S 2 interface. Furthermore, the tracheids of the tensile parts outermost of bending specimen were subjected to the longitudinal tension and shear coupling stresses that led to the two kinds of cracks occurring, including trumpet-shaped cracks in the S 2 layer, and S 1 /S 2 interface debonding.

show abstract

“…Babiak et al [12] prepared specimens made of spruce wood (Picea Abies L.) and oak wood (Quercus robur L.) with dimensions of 20 (radial) × 20 (tangential) × 300 cm (longitudinal) to be tested in a Three and four point bending test to find out some mechanical properties of the species studied, between them, the modulus of elasticity, according to the standard EN 310 [13], for measurements in three-point bending, the support span was adjusted to l 0 =12×H. This work objectify the study of the correlation between the longitudinal modulus of elasticity determined in the 3-point static bending test with a span length between supports of 14H and 21H (H = height of the cross-sectional area of the specimen).…”

Section: Introductionmentioning

confidence: 99%

Correlation of Bending Test Varying the Length Between Supports to Determine Longitudinal Modulus of Elasticity

Rodrigues¹

2019

IJMSA

View full text Add to dashboard Cite

The large amount of wood in Brazil related to the numerous uses of this material stimulates many studies to be carried out in order to use this raw material increasingly in a rational and adequate way. Compared with concrete and steel, wood presents an excellent relation between mechanical strength and its mass, beauty, low energy consumption for its processing, good thermal insulation and easy workability. In order to make the best use of wood, this work proposes to study the correlation between the values of the longitudinal modulus of elasticity (E) obtained in the 3-point bending test with a 14H and 21H (H = height of cross-sectional area) of specimen measurement between the supports. The data were analyzed through linear regression analysis, thus, three correlations were calculated between values from 14H of span length to the other 21H of span length in the test for a particular correlation of each hardwood species (Peroba Rosa and Eucalyptus Tereticornis) and the third one was generalized for the use in more hardwood species. Thus, the correlation of the longitudinal modulus of elasticity for the species of the hardwood group was possible for: Peroba Rosa (Aspidosperma polyneuron) with 35 specimens and Eucalyptus Tereticornis (Eucalyptus tereticornis) with 33 specimens.

show abstract

Modulus of elasticity in three- and four-point bending of wood

Cited by 44 publications

References 6 publications

Consolidation of Fir Wood by Poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) Treatment: Study of Surface and Mechanical Characteristics

Consolidation of Fir Wood by Poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) Treatment: Study of Surface and Mechanical Characteristics

The fracture mechanism of softwood via hierarchical modelling analysis

Correlation of Bending Test Varying the Length Between Supports to Determine Longitudinal Modulus of Elasticity

Contact Info

Product

Resources

About