What are the mechanical properties of wood?
The mechanical properties of wood include strength in tension and compression (as measured in axial and transverse directions), shear, cleavage, hardness, static bending, and shock (impact bending and toughness).
What are the 12 properties of wood?
The main physical properties of wood include: color, luster, texture, macro-structure, odor, moisture, shrinkage, internal stresses, swelling, cracking, warping, density, sound – electro – thermal conductivity.
What are the strength properties of wood?
Relationship between Mechanical Properties and Anatomical Structure of Wood
Property | n | A90/A0 |
---|---|---|
Tensile strength | 1.5–2 | 0.04–0.07 |
Compression strength | 2–2.5 | 0.03–0.40 |
Bending strength | 1.5–2 | 0.04–0.10 |
Modulus of elasticity | 2 | 0.04–0.12 |
What is the durability of wood?
Durability of Wood-Framed Buildings Wood has the ability to absorb and release moisture, and is resistant to many of the chemicals and conditions that adversely affect steel and concrete, such as corrosive salts, dilute acids, industrial stack gases, sea air, and extreme climate variances.
What are structure and properties of wood?
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic material – a natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin that resists compression.
How does density affect the mechanical properties of wood?
As discussed in Lesson 1, density is an excellent indicator of wood strength; the higher the density the stronger the wood. However, a wood with a density of 600 may not be twice as strong as one with a density of 300. It depends on the strength properties being discussed.
Why is density important in wood?
Wood density has long been considered the most important wood quality attribute. To a large extent, wood density determines the suitability of a species for a specific end use. High-density wood is usually associated with high lumber strength and stiffness.
What is hardness mechanical property?
Hardness is just one mechanical measurement and properties such as toughness and strength need to be considered, as hard materials tend to have low toughness and can easily fracture. Hardness can be assessed by a number of techniques including indentation, scratch and rebound hardness measurements.
What is the strongest type of wood?
Generally acknowledged as the hardest wood, lignum vitae (Guaiacum sanctum and Guaiacum officinale) measures in at 4,500 pounds-force (lbf) on the Janka scale.
What are three properties of wood?
Growth Rings. Growth rings vary in width depending on species and site conditions.
What are the characteristics of wood?
It is highly versatile. It is relatively light in weight, yet has good strength in both tension and compression; and provides rigidity, toughness and insulating properties. It can be bent or twisted into special shapes, and it is readily worked, fastened and finished.
How does density affect wood?
Density is correlated to the mechanical properties of wood in that as density increases, the strength of wood increases. For visual grading purposes, density determinations are based on the number of growth rings per 25mm and the average amount of latewood in the growth rings.
How does density relate to the strength of wood?
As discussed in Lesson 1, density is an excellent indicator of wood strength; the higher the density the stronger the wood. However, a wood with a density of 600 may not be twice as strong as one with a density of 300.
What is high density wood?
HDF (High Density Fibreboard/Hardboard), sometimes referred to as HDF wood, is like MDF in that it is a man-made composite panel product that is manufactured from compressed wood fibres. It is a stronger, harder product than MDF with a typical density of up to 900kg/m3.
What are the mechanical characteristics of wood?
Wood is widely used for structural purposes. This fact sheet summarizes some of the basic concepts related to mechanical characteristics of wood, including viscoelasticity, compression, shear, bending strength properties and how such characteristics should be taken into consideration for an efficient practical design.
Does “clear” wood have mechanical properties?
David E. Kretschmann, Research General Engineer 5–1 The mechanical properties presented in this chapter were obtained from tests of pieces of wood termed “clear” and “straight grained” because they did not contain characteris- tics such as knots, cross grain, checks, and splits.
What is Chapter 5 in mechanical properties of wood?
Mechanical Properties of Wood CHAPTER 5 Mechanical Properties of Wood David E. Kretschmann, Research General Engineer 5–1 The mechanical properties presented in this chapter were obtained from tests of pieces of wood termed “clear” and “straight grained” because they did not contain characteris- tics such as knots, cross grain, checks, and splits.
What are the mechanical properties of a material?
Mechanical properties most commonly measured and repre- sented as “strength properties” for design include modulus of rupture in bending, maximum stress in compression parallel to grain, compressive stress perpendicular to grain, and shear strength parallel to grain.