What is gradation testing?
What is gradation testing?
A sieve analysis (or gradation test) is a practice or procedure used in civil engineering and chemical engineering to assess the particle size distribution (also called gradation) of a granular material by allowing the material to pass through a series of sieves of progressively smaller mesh size and weighing the …
What are types of gradation?
there are two main gradation types categorised by aggregate morphology, namely continuous gradation and gap gradation, or three types by air voids, namely dense gradation, open gra- dation and semi-open gradation.
How do you find the grade of fine aggregate?
Cumulative percentage of weight retained on all the six sieves = 292 Fineness Modulus of Fine Aggregates = 292/100 =2.92 kg. Where “x” is the amount of fine aggregate (by volume)for 1 volume of coarse aggregate. Fc = Fineness modulus of coarse aggregate. F = Fineness modulus of desired mixed aggregate.
How do you do grading in aggregate?
The grading of an aggregate can be measured by what proportion of the aggregate, by mass, passes through different sized sieves. The grading of an aggregate can be altered by blending multiple aggregates of different gradings.
How is gradation calculated?
Determine the theoretical combined gradation from the individual gradations. This is done by multiplying the percent retained on each sieve for the individual gradations by the relative portion of the aggregate volumes. Then total the percent retained of each product for each sieve size.
What is the grading of aggregate?
Aggregate Grading – is a measure of how well distributed the sizes of the particles in an aggregate are. A well graded aggregate will have a good range of particle sizes and will have a fair representation from every size of particle.
What is the different grading of aggregates?
Grading Limit for Single Sized CoarseAggregates
| IS Sieve | Percentage passing for single sized aggregates of nominal size(mm) | |
|---|---|---|
| 80 mm | 100 | – |
| 63 mm | 85 – 100 | 100 |
| 40 mm | 0 – 30 | 85 – 100 |
| 20 mm | 0 – 5 | 0 – 20 |
Is code for grading of aggregates?
The aggregates are graded as per IS code 383, when the aggregate size is less than 4.75mm is called fine aggregate & more than 4.75mm is called coarse aggregate. The aggregate gradation is determined by the fineness modulus method where aggregates are passing through the sieve as per IS standard to classify its size.
Why is grading of aggregates important?
Grading of aggregates gives uniformity in the specific weight of concrete. Grading of aggregates reduces the chances of segregation in concrete. The graduation curve is also used to estimate the type of soil.
What are aggregate tests?
Aggregates are tested for strength, toughness, hardness, shape, and water absorption. In order to decide the suitability of the aggregate for use in pavement construction, following tests are carried out: Crushing test. Abrasion test.
What are the sizes of aggregate?
The usual range employed is between 9.5mm and 37.5mm in diameter. – Fine aggregates are usually sand or crushed stone that are less than 9.55mm in diameter. Typically the most common size of aggregate used in construction is 20mm. A larger size, 40mm, is more common in mass concrete.