Methods Of Sieve Size Analysis
Determination of article size is more important in Civil Engineering, as the particle size determines the effectiveness of final product.
The characters of particle such as bulk density, physical stability, permeability and many more are decided by its size. To determine the size distribution of particles, the sieve analysis test procedure is an effective method that prevailed from the past.
In sieve analysis, the particle size distribution is defined using the mass or volume. Sieve analysis is laboratory test procedure in which particles will move vertically or horizontally through sieve mesh.
Depending on the needs and particle material different sieving methods are available for the application. They are manual sieving method, mechanical sieving method, dry sieving method and wet sieving method.
Manual sieving method is carried out in places where there is no electricity and mainly used in, onsite differentiation among large and small particles. Mechanical sieving method is used in laboratories to assure the quality and this is the widely using method in present days.
In mechanical sieving the method can be classified into two further groups depending on their sieving movement as horizontal movement sieving method and vertical movement sieving method. The vertical movement sieving method is also known as throw-action sieving and vibratory sieving methods.
Dry sieving method is considered mostly and here the testing particles (specimen) are in dry state. Wet sieving method is considered when the particle that is going to be used is already exists as wet or suspension. Here, in the sieve shaker machine a nozzle will be provided to water the upper most sample material. But need some extra about the water concentration during this wet sieving experiment.
British Standard Sieving Test Procedure
Materials Needed: Specimen, sieve shaker, BS410 Standard sieves, 0.1g accuracy balance, oven, porcelain dish and spatula, receiving pan, cleaning brush and clock.
Procedure:
- Clean the sieves of sieve shaker using cleaning brush if any particles are struck in the openings.
- Record the weight of each sieve and receiving pan.
- Dry the specimen in oven for 3-4 minutes to get the dried specimen (ignore, if the specimen is already dried).
- Weigh the specimen and record its weight.
- Arrange the sieves in order as the smaller openings sieve to the last and larger openings sieve to the top. (Simply, arrange them to the ascending order of sieve numbers – No.4 sieve on top and no.200 sieve at bottom)- Sieve numbers and the particle sizes are provided below in a chart for further understanding.
- Keep the weight recorded specimen on the top sieve and then keep the complete sieve stack on the sieve shaker (Don’t forget to keep the lid and receiving pan).
- Allow the shaker to work 10-5 minutes – use the clock here..!
- Remove the sieve stack from the shaker and record the weight of each sieve and receiving pan separately.
Source: basiccivilengineering.com
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