IS USED BY DOTS WORLDWIDE, AND IN THE US, BECAUSE IT PERFORMS WITH BOTH 8 INCH and 12 INCH SIEVES.THIS HEAVY DUTY SIEVE SHAKER HANDLES LARGE VOLUMES OF AGGREGATES, AT REDUCED NOISE LEVELS.
COMMONLY USED SIEVE SHAKERS BASED ON THE ORIGINAL, "MARYANNE" AND, "RO TAP" SIEVE SHAKERS. THE DURATAP IS DESIGNED TO PROVIDE THE SAME HAND SIMULATION MOVEMENT AS THE ORIGINAL, BUT WITH A FEW RELIABILITY MODIFICATIONS.
A gradation test, or sieve analysis test, is a basic, but essential test, for aggregates, and determines the distribution of aggregate particles, by size, within a given sample, in order to determine compliance with design, production control requirements, and verification specifications.
The data can be used to calculate relationships between various aggregate, or aggregate blends, to check compliance, and to predict trends during production by plotting gradation curves graphically.
Used in conjunction with other tests, the sieve analysis is a powerful quality control tool.
For sifting purposes, particles larger than three inches are hand sieved. Between 3 inch and 3/4 inch particles, are sifted using a large screen shaker like the Gilson TS 1, or more recently, a heavy duty vibratory sieve shaker, like the Endecotts D 450. The advantage of the latter, is that it may be used for aggregate fines analysis as well.
A series of twelve inch sieves are generally used to separate materials between 1" and the amount retained on a #10 (2.0 mm) sieve. *AASHTO M92. Aggregate fines, defined as those that pass through the #10 sieve, are generally run on 8" or 12" Sieves.Tray shakers are not recommended for use with aggregate fines, so a separate sieve shaker is required.
Mechanical sieve shakers, if used, must provide a vertical or lateral and vertical motion to the
sieve, causing the particles thereon to bounce and turn so as to present different orientations to
the sieving surface. Sieve shakers must provide sieving thoroughness within a reasonable time.
Standard test method for flat particles, elongated particles,
or flat and elongated particles in coarse aggregate- Correlates with OCCHIO WIDTH & LENGTH Size parameters. For smaller particles, use ellipsoid width and length parameters.
Percentage of fracture in coarse aggregate- Correlates with Occhio BLUNTNESS Shape Parameter
Sieve Analysis- Correlates with Occhio INNER DIAMETER Size parameter
Measure Measure percentage of material coated- Color camera required