The General name of materials like sand, gravel, crushed stone that are used in concrete production is called aggregate. Aggregate that take place inside concrete approximately as volume of 60-75% is an important component. According to their grain sizes they are divided as thin ( sand, crushed sand…) and rough ( gravel crushed stone..) aggregates into two groups. The most important characteristics that are sought in aggregates are:

• Hard, durable and a space to be free,
• They do not include the weak grains (shells, wood, coal, ... etc),
• To be resistant to pressure and abrasion,
• Not to contain dust, soil and materials that may give harm to concrete,
• Not to include flat and long grains,
• Not to react harm with cement

Dirt of aggregates ( clay, silt, spindle, dust..) affects adherence negatively, this also increases the need of water. Sieve analysis of concrete aggregates, flatness, such as specific gravity and water absorption experiments should be done in appropriate periods and the quality continuity should be followed. The aggregates that will be used in concrete should be comply with TS 706.

AGGREGATE STANDARTS TABLE

EXPERIMENTS	ACCEPTANCE LIMITS	EXPERIMENT STANDARD	EXPLANATIONS
Grain Shape	8 mm üzerindeki yassı ve uzun taneler ağırlıkça %50'den çok olmalıdır.	TS-3614	. The small size of the largest grain size ratio is greater than 3 to one of them is called defective
Grain Strength	Bilyalı tamburla 100 dönüş sonunda ağırlıkça max %10.500 dönüş sonunda max %50 olacak.	TS-3694
Freezing Strength (Sodyum Sülfat)	In thin aggregates max %15 In rough aggregate max %18	TS-3655
Substances that give harm to hardness	Sugar,mica and soluble salts will not be available	TS-3821	Examined the compressive strength of concrete made with aggregates, compared to 85% lower than the compressive strength of concrete, the aggregate of the concrete hardening is assumed to contain harmful substances.
Sulfurous Compounds	Determined sulfate as SO3  max %1	TS-3674	Sulfurous compounds (alkali sulfates, like gypsum and anhidirit) is harmful to concrete.
Substances that give harm to steel	When water soluble chlorides are determined as chloride  max%0.2	TS-3732
Alkali Aggregate	Silica minerals react with alkali hidroxide ( kristobatit, tridimit, opal etc.) and Stones (sandstone with opal, obsidian,flint etc.) will not found	TS-3332 TS-2517	Prolonged length of mortar bars, 0.5% up to 6 months, 1 year, 1% should be the max. (TS-3322) Chemical methods in the region should be harmless. (TS 2517)
Washable Materials	63 micron sieve 0 / 4 mm 4% max, 1 / 4 mm up to 3%, 2 / 8 mm, 24/63 mm, max 0.5% max	TS-3527
Organic Origin Materials	In experiments with sodium hydroxide liquid color will not be dark yellow, brown or red	TS-3673
Light Materials	When coal or other tumescent materials are floated on 20kg/dm3 its weigth will not be more than %0.5	TS-3528

Concrete making materials within the largest ratio (75%) which aggregates (sand, gravel, crushed stone ..), natural resources increasingly depleted and standards, clean and high quality samples are difficult as a material, ready mixed concrete industry's strategic importance with each passing day increases. As it is stated at the II. National Symposium of Crushstone held in Istanbul in 1999, unless serious measures are taken in this field, in the near future even aggregate will be imported. In fact, especially in the Marmara region many quarries are engaged in activities to produce “ concrete aggregate” in our country. However, very few of them are aware of their work; very few have the certificate of conformity to standards, appropriate equipment and skilled personnel. They aim to serve as the concrete can not be useful to manufacturers, unconscious and primitive production methods they give the environment suffered irreparable damage. In addition to this confusion and gaps in legislation on the subject has become inextricable.

Today, many concrete producers from the market in accordance with standards organizations, high-quality aggregate for not providing the appropriate conditions as to set up units or companies, by operating quarries, aggregate, they go directly into the path generation.

Purpose is not only concrete itself, it is to monitor the quality process of other ingredients that mix with concrete except cement and to document these; Turkey Ready Mixed Concrete Association, members of the concrete mix to ensure that all materials into and out of compliance with the standards document calls, not documented in compliance with the standards of the concrete material is predicted not to be preferred.

 Aggregate production and use stardardization supply in the sector the problems can be solved in terms of Aggregate Producers Association (AGÜB) establishment and concrete as in the aggregate in the production, conformity to standards and quality targets conscious producers come together will be an important development in industry's future

I. Decripiton and Features

Concrete aggregates is a heap that concrete or mortar in the construction of cement and water mixture binder material brought to the organic, non-natural or artificial material usually 100 mm not exceed (or even the structure of concrete in most of the time 63 mm, not exceeding the size of ruptured or broken grains. Some examples of the various aggregates used in concrete construction are: sand, gravel, crushed stone, high-furnace slag, clay, pumice, perlite and fly ash obtained from fly ash aggregate. Aggregates constitute approximately 70-75% of the volume of concrete.

Concrete aggregate in the use provided the specifications of the early hardening of concrete 'volume change' prevention or reduction of hardened concrete 'corrosion resistance' to increase, the environmental impact against the 'resistance' to increase their own strength of the power because of its high concrete carry the load against the 'resistance' can provide income.

The aggregates stability, porosity, water permeability, mineral composition, grain form, gradiaiton, one of the surface roughness, the largest particle size, elastic modulus, thermal dilation coefficient, the aggregate of clay whether and aggregate cleaning as many properties of concrete durability type affects one or more that are used in concrete.

• Aggregate production centers, piles of concrete plants and aggregate storage and transportation of construction sites to pay attention to these issues is required;
• Measures should be taken to avoid contamination of aggregate grains. Care must be taken to avoid the entry of harmful substances and contamination of aggregates. While creating piles of aggregates if possible hard and clean ground should be chosen or aggregates should piled on this flor by preparing concrete floor. Aggregate piles can be settled on this ground previously by laying sand, gravel or rock fragments. Measures should be taken to ensure easy drainage of water in aggregate pile. It should be paid attention that loose soil particles surrounding should not mix between aggregate grains.
• Should not cause separations. During placing, storage or transport of aggregates, measures should be taken to prevent big aggregate and fine aggregate a stack of separate sets of courses by nearly 'separation (segregation)

II. Classification of Aggregates

1. Obtained according to the manner
2. According to grain size
3. Classification obtained according to the manner

A) Natural Aggregate ( Natural stone aggregate )
B) Artificial Aggregate ( Industrial product aggregate )

B.Classifying According to Size
A) Thin aggregate ( under 4 mm )
Sand
Crushed sand
Artificial sand
B) Big aggregate ( over 4 mm )
Gravel
Crushed stone
Artificial stone
C) Stone dust ( Filler ) ( under 0,25 mm)

1- 1. Appropriate strength and wihout space
2. Shapes of grains are important and do not include low grains ( l sea shells, wood, clay etcs )
3. Characteristics like pressure, adhesion, frost resistance, water absorption, specific gravity and abrasion should be good
4. Should not contain substances that may give harm to dust, soil and concrete
5. They do not include flat and long grain
6. They do not harmful reactions with cement

All the services’ life will be short strengths weak under pressure, abrasion fast that are not produced with the aggregates that do not have the above features.

• At concrete plants
• At surface coating
• At road construction
• At ground coverings
• At railways
• At hot asphalt consruction
• At airports, dam construction, sugar refineries