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Radial section of wood in which rays are shown Wood anatomy is a scientific sub-area of wood science , [ 1 ] which examines the variations in xylem anatomical characteristics across trees, shrubs, and herbaceous species to explore inquiries related to plant function, growth, and the environment.
In solid mechanics and structural engineering, section modulus is a geometric property of a given cross-section used in the design of beams or flexural members. Other geometric properties used in design include: area for tension and shear, radius of gyration for compression, and second moment of area and polar second moment of area for stiffness .
There is a strong relationship between the properties of wood and the properties of the particular tree that yielded it, at least for certain species. For example, in loblolly pine, wind exposure and stem position greatly affect the hardness of wood, as well as compression wood content. [30] The density of wood varies with species.
Wood is an example of an orthotropic material. Material properties in three perpendicular directions (axial, radial, and circumferential) are different. In material science and solid mechanics, orthotropic materials have material properties at a particular point which differ along three orthogonal axes, where each axis has twofold rotational ...
[citation needed] PSL can be made from any wood species, but Douglas fir, southern pine, western hemlock, and yellow poplar are commonly chosen [9] because of their superior strength. The product is manufactured as a 12-by-12-inch (300 mm × 300 mm) or 12-by-18-inch (300 mm × 460 mm) billet in a rectangular cross-section, which is then ...
Progressive bending and cracking would occur in parts of the tree undergoing predominantly tensile or compressive stresses were it not for the localised production of reaction wood, which differs from ordinary wood in its mechanical properties. Reaction wood may be laid down in wider than normal annual increments, so that the cross section is ...
Wood grain is the longitudinal arrangement of wood fibers [1] or the pattern resulting from such an arrangement. [2] R. Bruce Hoadley wrote that grain is a "confusingly versatile term" with numerous different uses, including the direction of the wood cells (e.g., straight grain, spiral grain), surface appearance or figure, growth-ring placement (e.g., vertical grain), plane of the cut (e.g ...
The properties of timber are non-linear and very variable, depending on the quality, treatment of wood, and type of wood supplied. The design of wooden structures is based strongly on empirical evidence. Wood is strong in tension and compression but can be weak in bending due to its fibrous structure.