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Project Management Year 1 > Materials > Flashcards

Flashcards in Materials Deck (89)
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1
Q

Hardwoods 6

A
Long-lasting
Angiosperms (seed vessel)
Longer to grow 
Most hardwood species are tropical 
Need to be managed sustainably
Deciduous trees
2
Q

Softwood 4

A

Gymnosperm (naked see)
60-120 years relatively shorter growth
1/3 of worlds wood / 80% of UK
From Conifers

3
Q

How many types of Timber

A

30,000

4
Q

Wood Properties 3

A

Low thermal conductivity - good heat storage
High strength - 2/3 of all houses timber frame
Low weight

5
Q

Anisotropic

A

Different properties when measured in different ways

Wood stronger across the grain

6
Q

Wood Conversion

A

Cut logs into sections

Finished by planing or sanding

7
Q

Tree Workings

A

Trunk gives structural strength
Bark prevents mechanical damage
Radical rays move food into sapwood for storage

8
Q

Potential Wood Damage

A

Fungi - Metabolising organic material (Wet/dry rot)
Insects
Fire Damage

9
Q

Fire Retardants

A

Reduce flaming of surface
Slows it down
Impregnation with leach-resistant chemicals
Surface coatings.

10
Q

Preserving Timber

A

Fungicides/Insecticides

Impregnation modification - Chemicals to fill gaps

11
Q

Properties of Steel (6)

A
High Strength 
Good Ductility 
High Stiffness
Suitable for prefabrication
Highly recyclable
Worked by sawing, drilling, flame cutting, welding bolting
12
Q

Steel

A

Alloy of Iron and Carbon
0.4% carbon 2x strength
1% carbon 3x strength
More carbon incr tensile (hard) not strength more brittle.

13
Q

Iron

A
Element 
Heated to 900
Allotropic
Hematite/Magnetite
Extracted with coal and limestone
14
Q

Cast Iron

A

Remelting Pig Iron w/ steel and cast iron scrap

Finished product has a high carbon content

15
Q

Pig Iron

A

Used to make Cast and Wrought Iron

4-5% Carbon

16
Q

Wrought Iron

A

Pig Iron heated with Iron oxide in a furnace

Carbon/impurities react with oxygen to form slag

17
Q

Cast Iron Properties

A
3-4% Carbon
Better than Wrought Corrosion resistant 
Brittle
Suitable for casting
Not suitable for Hot working
18
Q

Wrought Iron Properties

A
Low 0.15% High 0.5-1.5%
Good Resistance die to oxide layer
Reasonable tensile strength, Malleable and tough
Can be forged, complex work
Cannot be cast, tempered or welded
19
Q

Uses of Steel

A

Hot or cold rolled sections
Off site quality control
Rapid assembly

20
Q

Iron/Steel Corrosion

A

Destructive attacks by external elements
Water vapour (rust)/electrolysis/oxygen
Abrasion of protective coatings expose metal
Temperature change expan/cont may fracture coatings
Humidity > 70% will initiate rusting but occurs > 50%
Pollutants help hold moisture on the surface of the metal

21
Q

Protective Coating

A

Painting - rust and mill scale must first be removed
Vitreous enamel - molten enamel form corro-resis coating
Plastic coatings - coating PVC, acrylic
Steel needs a zinc pretreatment
Zinc is used to galvanise steel

22
Q

Zinc Coating

A

Spraying or dipping in molten zinc
Barrier to the environment
Better surface for welding/painting
Durability depends on thickness

23
Q

Steel Reinforcement in Concrete

A

Take the tensile stresses away from concrete
Carry proportion of the compressive stresses
Control fire

24
Q

Fire Protection Steel

A

Steel incombustible, strength reduced by high temps
Load bearing strength reduces
Structural integrity lost at 550
Intumescent paint, expand 25-30 times, 2 hour protection

25
Q

Concrete composition

A

Cement, Sand, Aggregate

26
Q

Slump Test

A

Determines workability on site

Indication of correct consistency

27
Q

Concrete Accelerators

A

Increases reaction between water and cement, set faster

Calcium Chloride

28
Q

Concrete Retarders

A

Decreases rate of setting
Reduces 28 day strength
Phosphates/hydroxycarboxylic acids

29
Q

Water-resisting admixtures

A

Hydrophobic

Stearates or Oleates

30
Q

Air-entraining Admixtures

A

Improve workability
Reduce risk of segregation
Increase frost resistance
Decrease compressive strength

31
Q

Foaming Concrete

A

Low density

32
Q

Concrete Failure

A
Chemical attack 
Frost - Freeze Thaw
Abrasion
Fire
Movement – heat & moisture, creep
Cracking/spalling from corrosion of steel reinforcement
33
Q

Concrete Chemical Attack

A

Leaching
Sulphate Attack
Alkali-Silica Reaction
Carbonation

34
Q

External Sulphate Attack

A
Water containing penetrates concrete
Seawater - Sea defences
Acid Rain
Extensive cracking
Expansion
Loss of bond between cement paste and aggregate
Loss of strength
35
Q

Internal Sulphate Attack

A

Sulphate included in concrete when mixed
Sulphate rich aggregates
Screening and testing should prevent this

36
Q

DEF

A

Delayed formation of the mineral ettringite
High early temps prevents normal formation of ettringite.
Expansion and cracking

37
Q

ASR

A

Alkali-Silica Reaction
React high alkaline cement + reactive silica in aggregate
Gel produces takes on water and leads to cracking
Over time

38
Q

HAC

A

High Alumina Cement
Calcium aluminates rather than silicates
Rapid strength development
However mineralogical conversion reduced strength
Increased vulnerability to chemical attack.

39
Q

Steel Carbonation

A

Increases susceptibility to chloride attacks

40
Q

Concrete Creep/Shrinkage

A

Long term deformation under sustained loads

Shrinkage depends on aggregate size

41
Q

Concrete Repair

A

Epoxy resin

42
Q

How Glass is made

A

High melting/viscosity reduced by adding sodium oxide
Reduces it from 1700
Reduces energy and cost of manufacture

43
Q

Float Glass

A
Thinner 6mm or 0.4mm/25mm
Molten glass poured on molten tin 
Floats on tin, evenly spread
Thickness controlled by pour speed
Annealing (control cooling) exit as 'fire' polished product
Virtually parallel surfaces
Can be tinted
44
Q

How Float Glass is made

A
Raw Material Feed
Melting Furnace
Float Bath
Cooling Lehr
Continuous ribbon of glass
Cross Cutters
Large plate lift-of devices
Small plate lift-of devices
45
Q

5 Main Glass Groups

A
Soda-Lime Glass - Bulbs/Containers
Quartz Glass - High melting
Borosilicate glass - Chem resistant
Lead glass - Low Melting radiation shielding
Alumino-silicate glass - Glass fibre
46
Q

Glass Properties

A
Light transmission •  
Refractive index
Thermal properties 
Strength
Hardness - abrasion resistance
Durability - weathering
Fire resistance
47
Q

Gas Filled Glass

A

Argon gas

Lasts 15-20 years

48
Q

Recycled Glass

A

Landfill tax doubled in 2009
Fibreglass insulation
Remelting
Fine Aggregate

49
Q

4 Material Considerations

A

Suitability
Durability
Reliability
Sustainability

50
Q

Triple Bottom Line

A

Social
Economic
Environmental

51
Q

Construction Stat

A

50% of all materials globally used in construction

UK 200m tons of waste in 2012

52
Q

Building Cycle

A
Extract Raw Materials
Primary/Secondary Manufacture
Construction
Building Use
End of life
Demolish
53
Q

Waste Hierarchy

A
Landfill
Recover energy
Recycle/Compost
Re-use
Reduce
54
Q

4 R’s + D

A
Reduce
Re-use
Recycle
Recovery - (energy)
Disposal
55
Q

OSP

A

Off Site Construciton
Manufacture away from place of installation
Standardisation/Pre-Assembly
Occur all year round increase productivity
Rapid on site construction/improve time predictability
Quality control

56
Q

Non-Volumetric Construction

A

Assembled within a factory

Don’t enclose usable space, flat/two- dimensional

57
Q

Volumetric Construction

A

Pre-assembled Pods (Kitchen/bathroom)

3 Dimensional space

58
Q

Closed/Open Systems

A

Closed - Combine w/ components from same manufactur
Open - More Flexibility, can combine with others
Need to be standard Sizes

59
Q

Why Prefabrication

A

Quickly made water tight, early installation of services
Some modular systems have services incorporated
Factory better quality control and in theory zero defects

60
Q

Factory Fabrication

A
Quickly address skill shortages
Greater build cost accuracy 
Reduce on-site time/injury
Waste minimised
Less damage to components/no on site storage
Enable integration of BIM with more ease
61
Q

Prefabrication Problems

A

Factory specific on-site foundations specific

62
Q

Walter Segal Method

Huf Haus

A

Timber primary design and modular
Standardised - no waste, cut/alter material, reduce cost
Reduce wet trades, concrete plastering and bricklaying
5 trained men in 6 days

63
Q

EIA’s

BREEAM

A

Environmental Impact Assessment
Met environmental standards
Social/economic impact considered

64
Q

Portland Cement

A

1824 - Joseph Aspdin
Heated mixture of clay & chalk gave hydraulic cement
Mix burnt limestone + clay more calcined until CO2 gone
Material ground into fine cement powder

65
Q

Portland Cement Properties

A

Excellent strength
Stronger than Roman cement
5x stronger than hydraulic lime

66
Q

Portland Cement Development

A

Rotary Kilns
Addition of gypsum control setting
Use of ball mills to grind clinker and raw materials

67
Q

Hydraulic Lime

Non Hydraulic Lime

A

Limestone with reactive clay, hydration similar properties Portland cement
Higher Clay stronger and less permeable 18-25%
No clay non hydraulic

68
Q

5 Types of Cement

A
Portland Cement 
Portland-composite Cement
Blast furnace Cement
Pozzolanic Cement
Composite Cement
69
Q

Sustainability in Concrete

A

Reduce amount
Low embodied C - Heat eff, diff fuels, Clinker substitution
Use of recycled materials
Carbon capture and storage

70
Q

Thermosetting
Thermoplastics
Elastomers

A

Synthetic polymers can be:
Thermosetting - harden on heat and do not re-melt
Thermoplastics - soften and melt on heating
Elastomers - Rubber retain original shape

71
Q

4 Mineral Constitutions of Cement

A

Alite
Belite
Aluminate
Ferrite

72
Q

Cement Clinker

A

Clinker a nodular materials
Large rotating drum containing steel balls
Gypsum ground in to control setting properties

73
Q

Clinker Process

A
  • Clinker cools, liquid crystal = aluminate, ferrite low belite
  • Fast cool good - lots hydraulic react silicates + small, intergrown, aluminate and ferrite crystals.
  • Slow cool less hydraulic react silicates + coarse crystals of aluminate and ferrite - over-large aluminate crystals can lead to errattic seeng of cement.
  • Very slow cool, alite decomposes to belite + free lime.
74
Q

Thermoplastic Example

A

PTFE

ETFE

75
Q

Thermosetting Example

A

Phenolic Resins
Amino Acids
Polyester Resins

76
Q

Epoxy Resin

A
Thermoset
Adhesive
Good electrical insulator 
Hard / brittle unless reinforced
Resists chemicals well
77
Q

Polyester Resin

A
Thermoset
Stiff / hard / brittle unless laminated
Good electrical insulator 
Resists chemicals well	
Casting and encapsulation 
Bonding of other materials
78
Q

PTFE

A
Thermoplastic
Resistant to chemical attack
Light in weight
Not brittle
Inexpensive
Adaptable
Cause minimal tissue reaction
79
Q

ETFE

A
Thermoplastic
High corrosion resistance
Strength over a wide temperature range
High melting temperature, 
Excellent chemical / electrical / high-energy radiation resis
80
Q

Elastomeric

A

Undergo large deformations / high elasticity
Large chain molecules twisted/coiled random manner
Rubber

81
Q

Additives

A

Added to improve desired properties
Plasticisers - increase flexibility
Fillers - Reduce cost, improve fire resistance, chalk/sand
Pigments - Dyes/pigments added
Stabilisers - Reduce degradation by absorbing UV light
Flame retardants
Heat Stabilisers - work same under increased heat

82
Q

Admixture

A
Modify setting/hardening properties of cement
Accelerators
Air-entraining - lightweight blocks
Retarding
Water reducing - plasticisers
83
Q

Clay and Clinker

A

From clay reactants in the kiln of Lime, Silica, Alumina and iron produce the four mineral

84
Q

Glass additions

A

Soda - reduce melting temp of silica
Flurospa and soldium sulphate - reduce bubbles
Calcium/magnesium - stronger glass

85
Q

Paint component

A

Pigment - colour
Binder - bind to surface
Solvent - control properties of paint for application
Extender - go further

86
Q

Plastic Sustainability

A

Un recyclable plastics

Reduce different types, easier to recycle

87
Q

Unfired Brick

A
Air dried
Reduces shrinkage 
Improves strength
Low embodied energy
Easier to recycle
No moisture resistance more sustainable
88
Q

Stone

A

Igneous - Granite
Metamorphic - Marble (limestone)/slate (clay)
Sedimentary - Limestone/clay

89
Q

Brick Creating

A
Press, wire cut, moulded
Dried
Kiln
3 different temperatures
100 water, 400 burning carbon matter, 900 sintering