3/4" Dolomite
3/4" Dolomite
(OP)
I specified the use of "3/4" dolomite" for final grading of a site. What I get from the contractor is "well graded dolomite" in accordance with ASTM's standard size #57 which, according to the contractor, is graded 3/4" stone. The average size of dolomite delivered is significantly smaller than 3/4".
I did not specifically say "well graded" "graded" or "average" when refering to dolomite. Based on my specification of... 3/4" dolomite, is that enough to turn down this delivery?
I did not specifically say "well graded" "graded" or "average" when refering to dolomite. Based on my specification of... 3/4" dolomite, is that enough to turn down this delivery?





RE: 3/4" Dolomite
Well Graded is a USC subclassification relating to the uniformity of the sample; it does not specify a diameter.
Have the contractor supply a certified bill of lading ("ticket") for the delivery. If the d50 is not 3/4" you can turn it down. If it is 3/4", you can't.
RE: 3/4" Dolomite
Is there a reason to specify the 3/4" dolomite vs a well graded stone?
RE: 3/4" Dolomite
RE: 3/4" Dolomite
RE: 3/4" Dolomite
RE: 3/4" Dolomite
lha - Your AASHTO #57 descirption is dead on with the ASTM 57 description I have.
BigH - You are absolutely right!! At my company, we have standard boilerplate specifications for certain jobs/mateirals/etc. that we refer to when preparing a new spec. When I was writing this specification two years ago, I was more concerned with the details of the concrete and steel portions of the job than I was with the grading. Not to trivialize it, but dolomite was the absolute least of my worries.
Looking over some old specs involving dolomite, with the exception of one project, all specifications simply required " 3/4" Dolomite". I guess we've just been lucky all these years. Either that, or consistently duped. Either way its not something i'll leave to chance in the future.
Thanks to all for your assistance
RE: 3/4" Dolomite
As BigH said, why not specify what you want? There's no reason to be vague in a specification unless you don't know what you want or need, in which case you shouldn't be specifying it without some help. Further, don't specify something without knowing the parameters. If you specify a No.57 stone, it should be properly specified to comply with ASTM C33, Gradation 57. This incorporates more than just the size range of the gradation....it incorporates durability and reactivity issues as well. If you want a well-graded material, then specify according the the Unified Classification System or some other accepted engineering classification criteria for aggregate or soil (in your case you apparently wanted a GW, with max. size 3/4").
What you specified is not clearly rejectable. I would argue that you were unclear and that the contractor met the generally understood criteria of a "near 3/4" stone commonly used for your application. You'd be hard pressed to refute it without a better specification.
RE: 3/4" Dolomite