Sieve analysis helps to determine the particle size distribution of the coarse and fine aggregates by sieving. In this we use different sieves as standardized by the IS code and then pass aggregates through them and thus collect different sized particles left over different sieves.
Use SFN 9987 or 2455 to record all information. All weights are recorded to the nearest 0.1 g. Dry the sample according to T 255 at a temperature of 230 ± 9°F (110 ± 5°C).
Select sieves to furnish the information required by the specifications covering the material to be tested. Use of additional sieves may be desirable to prevent the required sieves from becoming overloaded.
The quantity retained on any sieve, with openings smaller than the No. 4 sieve, at the completion of the sieving operation shall not exceed 4 g per sq.in. of sieving surface area. If this occurs it is considered overloading of the sieve. The overload amount for an 8" diameter sieve is 200 g.
The quantity retained on any sieve, with openings of No. 4 and larger, at the completion of the sieving operation shall not exceed 2.5 times sieve opening times effective sieve area. If this occurs it is considered overloading of the sieve. The following table shows the maximum amount of material to be retained on a sieve before being considered overloaded.
Nest the sieves in order of decreasing size of opening from top to bottom and place the sample on the top sieve. Agitate the sieves by hand or by mechanical apparatus until meeting the criteria for adequacy of sieving.
When using a mechanical shaker, place the sample in the stack of sieves and shake until not more than 0.5% by weight of the total sample passes any sieve during one minute. Approximately 10 minutes will be sufficient for most material. Use manual shaking of the material on any one sieve to check on the thoroughness of sieving by any mechanical shaker.
Remove the top sieve, brush the retained material into a pan, weigh and record. Be sure to thoroughly clean each sieve. Repeat this process with each succeeding sieve, brushing the material into individual pans, and record the non-cumulative weights. The following table shows the maximum amount of aggregate material to be retained on a sieve before being considered overloaded.
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