Materials Flashcards

Question

Concrete composition

Answer 1

Cement, Sand, Aggregate

Answer 2

Determines workability on site | Indication of correct consistency

Answer 3

Increases reaction between water and cement, set faster | Calcium Chloride

Answer 4

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

Answer 5

Hydrophobic | Stearates or Oleates

Answer 6

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

Answer 7

Low density

Answer 8

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

Answer 9

Leaching Sulphate Attack Alkali-Silica Reaction Carbonation

Answer 10

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

Answer 11

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

Answer 12

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

Answer 13

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

Answer 14

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

Answer 15

Increases susceptibility to chloride attacks

Answer 16

Long term deformation under sustained loads | Shrinkage depends on aggregate size

Answer 17

Epoxy resin

Answer 18

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

Answer 19

``` 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 ```

Answer 20

``` 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 ```

Answer 21

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

Answer 22

``` Light transmission • Refractive index Thermal properties Strength Hardness - abrasion resistance Durability - weathering Fire resistance ```

Answer 23

Argon gas | Lasts 15-20 years

Answer 24

Landfill tax doubled in 2009 Fibreglass insulation Remelting Fine Aggregate

Answer 25

Suitability Durability Reliability Sustainability

Answer 26

Social Economic Environmental

Answer 27

50% of all materials globally used in construction | UK 200m tons of waste in 2012

Answer 28

``` Extract Raw Materials Primary/Secondary Manufacture Construction Building Use End of life Demolish ```

Answer 29

``` Landfill Recover energy Recycle/Compost Re-use Reduce ```

Answer 30

``` Reduce Re-use Recycle Recovery - (energy) Disposal ```

Answer 31

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

Answer 32

Assembled within a factory | Don't enclose usable space, flat/two- dimensional

Answer 33

Pre-assembled Pods (Kitchen/bathroom) | 3 Dimensional space

Answer 34

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

Answer 35

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

Answer 36

``` 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 ```

Answer 37

Factory specific on-site foundations specific

Answer 38

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

Answer 39

Environmental Impact Assessment Met environmental standards Social/economic impact considered

Answer 40

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

Answer 41

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

Answer 42

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

Answer 43

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

Answer 44

``` Portland Cement Portland-composite Cement Blast furnace Cement Pozzolanic Cement Composite Cement ```

Answer 45

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

Answer 46

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

Answer 47

Alite Belite Aluminate Ferrite

Answer 48

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

Answer 49

- 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.

Answer 50

PTFE | ETFE

Answer 51

Phenolic Resins Amino Acids Polyester Resins

Answer 52

``` Thermoset Adhesive Good electrical insulator Hard / brittle unless reinforced Resists chemicals well ```

Answer 53

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

Answer 54

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

Answer 55

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

Answer 56

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

Answer 57

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

Answer 58

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

Answer 59

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

Answer 60

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

Answer 61

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

Answer 62

Un recyclable plastics | Reduce different types, easier to recycle

Answer 63

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

Answer 64

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

Answer 65

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

Materials Flashcards

(89 cards)