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