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This test method is used for evaluating the crushed content of gravel by determining the amount of fractured particles. For this method, a fractured face is an angular or broken surface caused by mechanical crushing. A face is considered a “fractured face” whenever one-half or more of the surface has been broken, with sharp and well defined edges, when looking directly at the fracture. A fractured particle is a particle having at least one fractured face.
1. Sieves - a 3/8 in. (9.5 mm) sieve having wire cloth conforming to AASHTO M-92
2. Oven or hot plate
3. Balance - A balance having a capacity of at least 5000 grams, accurate to 0.5 gram
Obtain a representative sample by appropriate methods as detailed in Materials IM 301. The weight of the representative sample after reduction must be large enough to yield a minimum of 2500 grams of material after sieving over a 3/8 in. (9.5 mm) sieve.
C. Sample Preparation
The sample must be sieved on the 3/8 in. (9.5 mm) sieve and the material passing the 3/8 in. (9.5 mm) sieve is discarded.
D. Test Procedure
4. Weigh the total amount of fractured particles to the nearest 0.5 gram.
5. E. Calculations
1. Calculate the percent of fractured particles based upon the total mass (weight) of the sample [plus 3/8 in. (9.5 mm)].
PERCENT FRACTURED PARTICLES =