Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Engineering Materials > Timber Technology > Flashcards

Timber Technology Flashcards

1
Q

What is the centre of the tree called?

A

The Pith. It is not very good wood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Dead Part of the three trunk?

A

Heartwood. Protects from fungal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is Sap Wood?

A

Nutrient Part of the tree. Living

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Two Main Classes of Wood Species?

A

Softwood and Hardwood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Soft Wood Characteristics?

A
  • Softer
  • Easier to Handle
  • Does not split when nailed
  • Popular as sawn Timber
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Softwood Trees?

A

Evergreen Trees such as Pine and Fir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Hardwood Trees?

A

Deciduous trees such as:

  • Mahogany
  • Oak
  • Maple
  • Gum Trees
  • Walnut used in high quality furniture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which direction is shrinkage least likely to occur?

A

Longitudinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Two types of shrinkage?

A

Tangential - Results in timber stressing

Radial -

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How Does Cupping occur?

A

When grains of wood are at angles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What percent mark does shrinkage occur?

A

25%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is wood dried/seasoned?

A

Kiln drying:

  • Steam
  • LPG Gas
  • Solar
  • Off cuts

Air drying

Other:

  • Chemical
  • Microwave
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is EMC?

A

Equilibrium Moisture Content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is external/inland EMC?

A

15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe EMC flows?

A
  • Wet atm/Dry Wood = Moisture moves to wood
  • Dry Atm/Wet Wood = Moisture moves from wood
  • Wood at EMC = No moisture movement to/from wood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Benefits of Seasoning?

A
  • Better Resistance to decay by fungi
  • Improved resistance to weathering
  • Stale in dimension; Creep Alleviated; Protective coating adheres better
  • Strength Improves
17
Q

What are the timber products?

A
  • Sawn Timber
  • Laminated Veneer Lumber (LVL)
  • Plywood
  • Hardboard
  • Glulam
18
Q

Sawn Timber Examples. (Probably won’t examine)

A
  • Stump: Foundation of houses
  • Bearer: Bears load of house
  • Floor Joist: Prevent bearer from bending
  • Stud: Wall Timber
19
Q

How is LVL made?

A

Timber is sawn into thin piles (Laminates) along the direction of the fibre

20
Q

What is Plywood?

A

Similar to LVC but the fibres in adjacent sheets are orthogonal directions (Criss cross)

21
Q

Difference between plywood and LVL?

A
  1. Alternative directions in plywood

2. Plywood is a sheet product whereas LVL is a beam

22
Q

What is hardboard?

A

Hardboard is a compressed composite board

23
Q

What is Medium Density Fibreboard (MDF)?

A

MDF is a type of hardboard which is made from wood fibres glued under heat and pressure

24
Q

What is Glulam (Glue Laminated Timber)?

A

Plain saw timber bits glues together, enabling curved and tapered features to be achieved

25
Q

What is cross laminated timber?

A

Plain sawn timber put into a panel. They are in layers. Sticking together timber. Used for big buildings. Layered in different directions. Alternating pattern makes a plate. We want stiffness in multiple directions.

26
Q

Sorting timber classifications?

A

Appearance grading and Structural Grading

27
Q

Structural Gradings Methods?

A

Visual stress grading
Machine Stress Grading
Proof Grading
Quality Control

28
Q

Most common timber grade?

A

F7

29
Q

Visual Stress Grading Characteristics?

A
  • Size of knots relative to specimen
  • Borer Holes
  • Termite Galleries
30
Q

Why are knots problems?

A

They change grain direction. This can cause localised weak spots

31
Q

Durability Issues?

A
  • Weathering
  • Decay with Fungi
  • Termites and bores
  • Countering Measures
32
Q

Weathering issues?

A
  • Bleaching and erosion of surface
  • Loosening of timbers
  • Opening of cracks
  • End of lumbers most vulnerable
  • Metal connectors are prone to corrosion
33
Q

Fungi occurs at:

A
  • M.C >20%
  • Presence of oxygen
  • Ideal at 25-40deg C
  • Sapwood at periphery is more vulnerable
34
Q

Termite and bores facts:

A
  • Hazard level increases with latitude

- End of member is most vulnerable to attack

35
Q

Countering Measures:

A
  • Sheltering and protective
  • Isolation from ground
  • Moisture control
  • Use durable timber specie
  • Chemical treatment
36
Q

Difference between glulam and LVL?

A

Glulam uses plain sawn timber stuck together with reasonable thickness whereas LVL uses thicker ones stuck together

Engineering Materials (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions