B.F. Bachelor of Forestry Wood Science and Technology 2 — Questions and Answers
Question 1: What is 'modulus of rupture' (MOR) in wood mechanics?
- The stiffness of wood measured in compression
- A measure of the maximum load a wood beam can carry in bending before failure (Correct answer)
- The resistance of wood to axial tension
- The hardness of wood surface measured by indentation
Correct answer: A measure of the maximum load a wood beam can carry in bending before failure
Modulus of rupture is the calculated maximum bending stress at the point of failure, used to characterize the bending strength of wood.
Question 2: What is 'wood preservative treatment' designed to do?
- Improve the color and appearance of wood for furniture
- Protect wood from decay, insects, and marine borers to extend its service life (Correct answer)
- Increase the specific gravity of low-density species
- Speed up the drying process in kiln operations
Correct answer: Protect wood from decay, insects, and marine borers to extend its service life
Wood preservative treatment impregnates wood with chemicals that resist biological degradation by fungi, insects, and marine organisms, extending product service life.
Question 3: What is 'cross-laminated timber' (CLT)?
- A traditional log cabin construction method
- A mass timber panel product made of layers of lumber stacked at right angles and glued together (Correct answer)
- Plywood made from tropical hardwoods
- Finger-jointed lumber reinforced with steel rods
Correct answer: A mass timber panel product made of layers of lumber stacked at right angles and glued together
CLT is an engineered wood panel made by gluing layers of dimension lumber with adjacent layers perpendicular, creating a strong, dimensionally stable product used in mass timber construction.
Question 4: Which defect most reduces the strength of structural lumber?
- Mineral streaks
- Knots (Correct answer)
- Slight grain slope variations
- Color variation from heartwood to sapwood
Correct answer: Knots
Knots interrupt grain continuity and create stress concentrations, significantly reducing the bending and tensile strength of structural lumber.
Question 5: What is 'fiber saturation point' (FSP) in wood science?
- The maximum amount of water a tree can absorb through its roots
- The moisture content at which cell walls are fully saturated but no free water exists in cell cavities (Correct answer)
- The point at which wood begins to decompose
- The humidity level at which wood stops shrinking
Correct answer: The moisture content at which cell walls are fully saturated but no free water exists in cell cavities
The fiber saturation point is approximately 28–30% moisture content and marks the boundary below which shrinkage and strength changes occur as moisture content changes.
Question 6: What is 'glulam' (glued-laminated timber)?
- A chemical adhesive used in plywood manufacturing
- Structural timber made by gluing together layers of dimension lumber with the grain parallel (Correct answer)
- Laminated veneer lumber used for furniture
- A preservative-treated wood product for ground contact
Correct answer: Structural timber made by gluing together layers of dimension lumber with the grain parallel
Glulam is an engineered wood product made of individual lumber laminations bonded with structural adhesives, allowing production of large, strong members from small-dimension lumber.
B.F. Bachelor of Forestry Wood Science and Technology 2
What is 'modulus of rupture' (MOR) in wood mechanics?