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Flashcards in aggregate Deck (19):

how many tonnes does ON consume of aggregate annually?

155 million


name 6 uses of aggregate

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


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


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


what is the 'over burden' referred to ?

layer of top and sub soil over top of the gravel


describe 3 aggregate processing methods

crushing, screening and washing


describe grade of aggregates

1. fill
2. sand fill


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


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


what type of material comes from gravel pit aggregates?

-granite based


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


how are materials screened

- dumped into vibrating screen


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)


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


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"


why wash aggregate?

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


what material is found in quarried aggregates?



what 2 benefits from crushing stone?

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


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