Materials Science

Question 1

Service life

Answer 1

Specified to meet the users requirement

Question 2

Design life

Answer 2

The period of use intended by the designer

Question 3

Examples of modes of deterioration

Answer 3

Concrete or masonry: Moisture penetration followed by chemical action or frost damage
Metals: Corrosion (e.g. damp conditions)
Timber: Fungal decay, rot, insect attack

WATER IS A COMMON FACTOR IN MOST CASES

Question 4

Steel + Oxygen + Water =

Answer 4

Rust

Question 5

High alkali cement + reactive aggregate + water =

Answer 5

AAR - Alkali-Aggregate Reaction eg alkali silica reaction

Question 6

What are the four stages of construction projects

Answer 6

1) Design - the designer see.cuts materials appropriate to a structures : form and contain, intended lifetime and physical environment
2) Construction - Safety of the workforce and quality of the end product should be key considerations during construction
3) In service - Materials require regular maintenance
4) End of life (demolition) - reuse and recycling of the material as well as safety of the personnel will be of significant importance

Question 7

The construction design and management regulations (2015) considers the role of?

Answer 7

• The client
• Designers
• Contractors

Question 8

All materials must perform to an acceptable standard in regards to:

Answer 8

• Resisting the spread of flames
• Release of hazardous substances
• Retaining structural stability in a fire situation

Question 9

Combustion requires all 3 of?

Answer 9

• Fuel
• Oxygen (oxidising agent)
• Heat/ignition

Question 10

Examples of passive protection

Answer 10

Fire resistant lining boards (e.g. gypsum plasterboard)

Question 11

Example of active protection

Answer 11

Smoke ventilation, alarm systems and sprinklers

Question 12

How are materials affected by high temperature?

Answer 12

• Steel softens
• Concrete expands and can spall (material breaks into pieces and partially cracks below the surface causing surface to come off)

Question 13

Land. Asked primary extraction can be further sub divided as?

Answer 13

1) Hard rock which is quarried and then crushed
2) Digging sand and gravel from areas where it has been deposited

Question 14

Hard rock examples

Answer 14

• Igneous rocks (including granite, ‘Elvan’ (dolerite which occurs in ‘dykes’)
• Sedimentary (well cemented sandstone, some limestone)

Question 15

Soft rocks examples

Answer 15

• Anything that is weakly cemented and crumbly
• Skate or shale which is fissile
• Mudstone, which tends to revert to the clay from which it was originally formed over time especially when broken into small pieces

Question 16

Soil in the civil engineering definition consists of:

Answer 16

• Gravel (10mm in size)
• Sand (1mm in size)
• Silt (10um in size)
• Clay (1um in size)

Question 17

Iron can be found as?

Answer 17

Magnetite (Fe3O4)
Haemetite (Fe2O3)

Question 18

What is smelting?

Answer 18

Process of heating ore in a blast furnace to extract the base metal

Question 19

Iron ore + coke =

Answer 19

Iron + CO2