Quantitative Characteristics of Local Strain Fields in a Top-Liner Board Sample under Uniaxial Tension
Journal Title: Lesnoy Zhurnal (Russian Forestry Journal) - Year 2020, Vol 10, Issue 1
Abstract
The paper presents the method for quantifying the distribution of local tensile (longitudinal), compressive (transverse) and shear strains in a sample of pulp and paper material. The results of its use for the sample of top-liner board when uniaxial tensile testing are provided. Applying this method, we have determined the values, the degree of heterogeneity and change patterns of local strains in inhomogeneous and anisotropic structure of the sample, depending on the total strain and the direction of fiber orientation. The method is based on constant-speed tensile testing of samples with a pre-applied dot matrix to their surface. The test is accompanied with photo fixing and recording a load-elongation curve. The coordinates and displacements of dots are determined by means of the specially designed software. The analysis of data and calculation of local deformations are performed by finite elements method (FEM) algorithms. The outcomes have shown that the local longitudinal deformations increased, transverse – decreased, and shear – had their maximum at 45° to machine direction (MD) when increasing the angle of preferential fiber orientation to MD in the board samples. The rise of the average absolute values of all components of local strains when increasing total deformation in the sample was confirmed. As it has been found, the heterogeneity of local strains, estimated through the standard deviation, rose when increasing their absolute value; the trends of changing depend on the fiber orientation direction in the sample structure.
Authors and Affiliations
A. N. Romanova, Ya. V. Kazakov, A. V. Malkov
Keywords
Related Articles
- EP ID EP683252
- DOI 10.37482/0536-1036-2020-1-180-189
- Views 624
- Downloads 0
Spatiotemporal Structure Features of a Pine Stand on the South Slope of the Eastern Sayan Mountains
Due to relatively long development and long life of forest-forming species most of the conclusions on stand dynamics are based on the data collected by indirect methods of comparative research and analysis of cenosis for...
Stand Structure of Northern Taiga Pine Forests
In Northern taiga conditions pine forests occupy about 1.8 mln ha of the territory of the Komi Republic and are mainly represented by sphagnum, green-moss and lichen forest types. The studies were carried out at the Zele...
Variability in Elemental Composition of Conifer Tree Rings
Distribution of chemical elements in tree rings bears important information on various biogeochemical processes. In order to achieve a reliable interpretation of the information, it is necessary to know the degree of var...
Features of the Growth and Structure of Pine Wood in the Felling Area and Under the Canopy of a Tree Stand in the Conditions of the Republic of Karelia
The intraspecific variability of the anatomical and hydraulic characteristics of xylem in the undergrowth in Scots pine (Pinus sylvestris L.) has been assessed during natural regeneration in the felling areas and under t...
Root Nutrition, Photosynthesis, and Net Primary Production in Tree Stands of the genus Picea at the Organism Level within the Range in Russia
A complex retrospective ecological and physiological analysis of the tabular data on the dry weight of stands of the genus Picea growing from the Northwest to the Russian Far East was carried out. Ecological and physiolo...