What are the 3 classifications of aggregates?

Classification of Aggregates as per Size and Shape -Coarse and Fine Aggregates
  • Rounded Aggregate.
  • Irregular Aggregates.
  • Angular Aggregates.
  • Flaky Aggregates.
  • Elongated Aggregates.
  • Flaky and Elongated Aggregates.

What are the various classifications of aggregates?

The different shapes of aggregates are: Rounded – Natural aggregates smoothed by weathering, erosion and attrition. Rocks, stone, sand and gravel found in riverbeds are your most common rounded aggregates. Rounded aggregates are the main factor behind workability.

What are the classification of aggregate based on density?

Classification of Aggregates. The variability in density can be used to produce concrete of widely different unit weights, see Table (1). The most common classification of aggregates on the basis of bulk specific gravity is lightweight, normal-weight, and heavyweight aggregates.

How are aggregates classified based on their sizes?

Based on the grain size, the aggregates are classified into two types. The fine aggregates are used in concrete as a filler material to fill the voids. The coarse aggregates are used in concrete to develop the strength of the element. The difference between the fine & coarse aggregate are listed below.

What is petrological classification of aggregate?

In that sense, the aggregates can be classified into two main categories: natural and crushed. In terms of origin, rocks are generally classified as igneous, sedimentary, or metamorphic based on how the rocks were formed over long periods of geological time.

What is coarse aggregate and fine aggregate?

Fine aggregates generally consist of natural sand or crushed stone with most particles passing through a 3/8-inch sieve. Coarse aggregates are any particles greater than 0.19 inch, but generally range between 3/8 and 1.5 inches in diameter.

How is aggregate size measured?

The most popular field test to measure the quality of aggregate is the sieve test. It is not possible to measure shape characteristic and other parameters by sieve analysis. Therefore, it is essential to develop rapid assessment techniques for quality control of aggregate.

What is the size of coarse aggregate?

When the aggregate is sieved through 4.75 mm size the aggregate is retained is known as coarse aggregate. Larger than 4.75mm size is coarse sand or aggregate, so coarse aggregate size arranging between 5mm to 256 mm or more.

What is single size aggregate?

Single-size aggregate is based on a nominal size specification. It contains about 85 to 100 percent of the material which passes through that specified size of the sieve and zero to 25% of which is retained in the next lower sieve. A graded aggregate contains more than one single-size aggregate.

How is the aggregate classified according to texture?

These aggregate category are generally hard, dense and fine-grained aggregates are smooth textured. These aggregates have lesser surface area because of lesser irregularities. When these aggregates are employed, lesser amount of cement is necessary for the lubrication purpose.

What is fine aggregate and its types?

Types of Fine Aggregate

Usually, sand, crushed stone, and crushed bricks are used as fine aggregate in concrete or pavement construction.

What is the properties of aggregate?

Basic properties of aggregates include mineralogical composition, surface texture and grain shape, dustiness, porosity, frost resistance, resistance to abrasion and polishing, and asphalt absorption capacity [1,2,3,4,5].

What is the flakiness index?

The flakiness index is defined as the percentage (by mass) of stones in an aggregate having an ALD of less than 0.6 times their average dimension. Flaky aggregates tend to produce seals with less voids due to their tendency to pack more tightly than cubical aggregates, consequently flaky particles require less binder.

What are the characteristics of coarse aggregate?

Coarse aggregates are irregular broken stone or naturally-occurring rounded gravel used for making concrete. Materials which are large to be retained on 4.7 mm sieve size are called coarse aggregates, and its maximum size can be up to 63 mm.

What is the difference between crushed and uncrushed aggregates?

Relevant to mention: uncrushed aggregate is cheaper than crushed aggregate. Consequently, concrete with uncrushed aggregates will be cheaper. It can be concluded that uncrushed aggregates are appropriate for medium grade concrete for better performance in terms of workability, strength and economy.

What is the flakiness index formula?

Determination Of Indices (Flakiness And Elongation)
IS Sieve size in mm
1. Flakiness Index ( C/A ) × 100 = %
2. Elongation Index ( D/B ) × 100 = %
3. Combined F1 & E1 ( 1+2 ) = %
Specified Limits:For road works 30% ( Max.) & For concrete work 25% ( Max. )

What is limit of flakiness and elongation?

Detailed Solution. The flakiness index of an aggregate is the percentage by weight of particles in it whose least dimension is less than 0.60 times their mean dimension. This test is not applicable to a size less than 6.3 mm.

Why flakiness index test is done?

The test Flakiness index of aggregate is used to determine the particle shape of the aggregate specimen and each particle shape being preferred under specific condition.