Oversize Particles in Borrow Material
Oversize Particles in Borrow Material
(OP)
We have a maximum 3' fill area that we area calling out maximum 12" lifts and that the material shall 100% pass a 4" sieve. The fill material will come from a granular onsite pit.
Since we are calling out in our spec 100% passing a 4" sieve I am assuming they would be required to pass all material through a Rock Screen in order to meet this criteria? Would oversize particles generally be allowed?
Since the 4" spec is called out would there be any rock correction neccessary in the proctor?
Since we are calling out in our spec 100% passing a 4" sieve I am assuming they would be required to pass all material through a Rock Screen in order to meet this criteria? Would oversize particles generally be allowed?
Since the 4" spec is called out would there be any rock correction neccessary in the proctor?





RE: Oversize Particles in Borrow Material
I hope that your specification also has further direction on the grain size distribution on particles passing the 4" scalping screen. What happens if all of the material passes a 4" sieve but is retained on a 1" sieve? That type of material would not be good for fill as raveling of finer particles would occur.
Preferably, your specification would state something to the effect of all material shall pass a 4" sieve and shall be consistently graded from that size to dust.
RE: Oversize Particles in Borrow Material
As far as the correction part of my question, even though the proctor test material will match what is used in the field (since its being screened) there is still a correction factor involved?
RE: Oversize Particles in Borrow Material
RE: Oversize Particles in Borrow Material
RE: Oversize Particles in Borrow Material
After the test is completed, a correction factor is applied based on the percentage of oversized (larger than 3/4") material. If I remember correctly, the oversize correction only applies if there is greater than 5% oversize and less than 30% oversize.
RE: Oversize Particles in Borrow Material
RE: Oversize Particles in Borrow Material
RE: Oversize Particles in Borrow Material
RE: Oversize Particles in Borrow Material
Now, if you want to partner / value engineer with the contractor and you decide that a few 6 inch rocks are OK and resulting in great cost savings which will then be split between the contractor and the owner - than it is a win-win situation.