Aggregates - Universitas Negeri Yogyakartapramudiyanto.blogs.uny.ac.id/wp-content/uploads/... · 10/1/2014  · Fine aggregate (FA) is defined as the material which will pass a No.

AggregatesConstruction’s Materials Technology

WHAT IS AGGREGATE?

a broad category of coarse particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosyntheticaggregates. Aggregates are the most mined materials in the world.

a component of composite materials such as concrete and asphalt concrete; the aggregate serves as reinforcement to add strength to the overall composite material.

aggregates are widely used in drainage applications such as foundation and French drains, septic drain fields, retaining wall drains, and road side edge drains.

Aggregates are also used as base material under foundations, roads, and railroads. In other words, aggregates are used as a stable foundation or road/rail base with predictable, uniform properties (e.g. to help prevent differential settling under the road or building), or as a low-cost extender that binds with more expensive cement or asphalt to form concrete

Natural sand, gravel and crushed rock aggregates are fundamental to the man-made environment and represent a large proportion of the materials used in the construction industry.

Aggregates are divided into two types: fine and coarse

Fine aggregate (FA) is defined as the material which will pass a No. 4 sieve and willbe predominantly retained on a No. 200 sieve.To increase workability and for economy as reflected by use of less cement, the FA should have a rounded shape. The purpose of the FA is to fill the voids between coarse aggregate (CA) particles and to modify the workability of the concrete. This characteristic of workability is discussed more in the description of finished concrete.

Coarse aggregate (CA) is a material which will be retained on the No. 4 sieve. In determining the maximum size of CA, other factors must also be considered. The coarser the aggregate use, the more economical the mix, as theaggregate costs less than cement. Larger pieces offer less surface area of the particles than an equivalent volume of small pieces. Use of the largest permissible maximum size of CA permits a reduction in cement and water requirements.One restriction usually assigned to CA is its maximum size. Large pieces can interlock and form arches or obstructions within a concreteform.

Fine aggregate

Coarse aggregate

SNI 03-1968-1990agregat halus terdiri dari :• ukuran maksimum 4,76 mm; berat minimum 500 gram;• ukuran maksimum 2,38 mm; berat minimum 100 gram.

Aggregat kasar terdiri dari :• ukuran maks. 3,5"; berat minimum 35,0 kg• ukuran maks. 3"; berat minimum 30,0 kg• ukuran maks. 2,5"; berat minimum 25,0 kg• ukuran maks. 2"; berat minimum 20,0 kg• ukuran maks. 1,5"; berat minimum 15,0 kg• ukuran maks. I"; berat minimum 10,0 kg• ukuran maks. 3/4" berat minimum 5,0 kg• ukuran maks. 1/2"; berat minimum 2,5 kg• ukuran maks. 3/8"; berat minimum 1,0 kg

Aggregates are produced for a number of reasons: • concrete aggregates,• road base and coverings and road stabilization,• asphaltic concrete aggregates and other bituminous mixtures,• construction fill, • concrete products, such as blocks, bricks, pipes, etc.,• plaster and gunite sands, • snow and ice control,• railroad ballast, • roofing granules, • filtration,• other miscellaneous uses.

Aggregate Usage Estimates Metric Tonnes(1,000 kg)

Typical tandem axle truck capacity 15

Average 1,500-square-foot home, when considering its proportional share of new streets, schools, churches, municipal construction projects and shopping centers

330

Single family residential - Vancouver 83Single family residential - Fraser Valley 166Six room house 91Low rise multifamily Development - PER UNIT 20

Commercial building - PER 93 m2 (1,000 ft2) 63

School or hospital 14,000Road and service construction per kilometre (2 lane) 18,500

4 lane US highway per 1.6 kilometres (1 mile) - (Meador, Layher 1998) 60,000

Rehabilitation of existing roadways, per kilometre 40 to 320