Aggregates

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Transcript of Aggregates

Submitted To:

Sir Shafiullah

Submitted by:

Huzaifa Shafiq (797)

Muhammad Abdullah Ijaz (798)

Afzaal Ahmad (850)

Numan Majeed (789)

Jamil Alam (801)

Umer Perveez (788)

Topic

Aggregates

Definition

Aggregate is a type of material used in construction, including sand, gravel, crushed tones etc.

Purpose of Aggregates

Strength Weight

Economically

Uses Of Aggregates

Concrete

Roads

Railway

Types Of Aggregates

Classification according to formationClassification according to size

Classification according to formatting

Natural AggregatesArtificial Aggregates

Natural Aggregates

Natural aggregates consists of rock

fragments that areUsed in their natural

state, or are used after mechanical

Processing such as crushing, washing, and

sizing.

Artificial Aggregates

For making special type of concrete we should make special type of

artificial aggregates. In these aggregates most

are light weight aggregates and heavy

weight aggregates

Classification According to Size

Fine AggregatesCoarse Aggregate

Fine Aggregates

“Fine aggregate” is defined as

material that will pass a No. 4 sieve and will, for the

most part, be retained on a No.

200 sieve

Types Of Fine Aggregates

Sand Stone dustCinderSurkhi

Sand

The first type of fine aggregate is Sand. Sand is

little particles of silica. Larger particles are

categorized as gravel; smaller particles are

categorized as silt or clay.

Types of Sand

Pit SandRiver SandSea Sand

Pit Sand

Sand from a pit, as distinct from river or sea sand. When

we washed and screened it is good

sand for general purposes.

River Sand

River Sand obtained from the banks and beds of rivers is also coarse

and fine. Coarse sand is best for use

in construction works.

Sea Sand

This sand is obtained from the shore of sea. The shape of this sand is rounded. Due to

water of sea it mixes with different

chemicals.

Stone Dust

This is the 2nd type of fine aggregate.

Stone dust is a finely crushed material used to fill in the spaces between

gravel

CinderCinder is the slag

from a metal furnace. Before use this slag we crushed this so

that its size remains in fine aggregate.

SurkhiSurkhi is finely

powdered burnt clay and

generally made from slightly under burnt

bricks.

Coarse Aggregate

Course aggregate basic material of the concrete. Crushed

stone or gravel used in concrete are called

coarse aggregate and it will not, pass when

it is dry through a sieve with ¼-inch-

diameter.

Types of coarse Aggregates

Stone BallastGravelBrick BallastClinker

Stone Ballast

Stone ballast produced by mining a suitable rock deposit

and breaking the removed rock down to the desired size

using crushers.

Gravel

Gravel is a mix of rock pieces or small

rocks. These are also called rounded

rocks.

Brick Ballast

For unimportant works we can use

brick ballast in concrete as coarse

aggregates. For this purpose well burned bricks are

chosen.

Clinker

Clinker is uses for produced Portland

cement. It may also be combined with other active ingredients or chemical admixtures

to produce.