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Flashcards in aggregate Deck (19):
1

how many tonnes does ON consume of aggregate annually?

155 million

2

name 6 uses of aggregate

-mulch
-septic field
-sports fields
-concrete products
-mortar
-joint sand for interlocking stone

3

what are 5 sources of aggregates

1. gravel pit
2. quarry
3. slag and mine refuse
4. rubble and refuse
5. pulverized concrete and asphalt materials

4

describe the aggregate extraction from a gravel pit process

1. strip topsoil
2. strip subsoil
3. extract garvel
4. but back the sub soil and topsoil for rehabilitation
ie stripping, extracting, processing, shipping, rehabilitation

5

what is the 'over burden' referred to ?

layer of top and sub soil over top of the gravel

6

describe 3 aggregate processing methods

crushing, screening and washing

7

describe grade of aggregates

1. fill
2. sand fill

8

what is fill

- not really an aggregate
-used for building up grade, under grass or backfilling holes or structures where drainage and structural strength are not issues

9

what is sand fill

-sandy non specific material
-building up grade or backfilling where some drainage is required and no large stone sizes are desired

10

what type of material comes from gravel pit aggregates?

-granite based

11

describe 4 types of granite based aggregate?

1. granular C: lower grade natural sand and stone sizes up to 6" --> covering sewer pipe or road sub base
2. granular B: cleaner well- graded natural sand and stone 4" in size --> sub base for roadbuilding or under concrete floor slabs
3. Fine Granular B: bank material screened to 2.5" for more uniform product and eliminate oversized stone --> base material and backfilling applications
4. Granular A: well grade sand under 3/4" --> strength while maintaining good drainage , concrete

12

how are materials screened

- dumped into vibrating screen

13

what is pit run ?

-free running stony gravel with well graded natural sand
-used for filling areas in wet conditions where product with more stone required (road base)

14

describe 6 types of sand

1. septic: water retention qualities
2. golf course
3. sports field sand
4. ice control sand
5. brick sand
6.concrete sand

15

describe 4 types of granite based screened products?

1. river rock 1"- 4"
2. pea stone 1/4"
3. roofing stone 1/2"- 1"
4. drain stone 3/4"- 2"

16

why wash aggregate?

-separates sand from stone and removes impurities
-more $$

17

what material is found in quarried aggregates?

limestone

18

what 2 benefits from crushing stone?

1. reduced to workable size
2. jagged edges good for concrete and asphalt

19

name 6 quarried aggregates

1. 3/4 crusher run: 100% crushed stone, chips and dust --> base where drainage isnt issue
2. 3/4 clear: 100% crushed stone, 3/4" in size--> good drainage material, behind retained walls
3. limestone screenings: 100% crushed stone, 1/4" - dust --> highly compactable with high water holding capacity, can be used as pathway
4. High Performance Bedding: 100% chipped stone 1/4" in size --> good draining material, falls at compaction rate, good base material for interlocking patio
5. crushed oversize: 4" and under to dust --> strong sub base
6. HL6 stone: clear crushed stone --> asphalt