What does everyone use for a swell factor for something like shot/blast rock? We're hauling waste rock in a mine with 730s and Komatsu 35 tonners and seeing some funky average load volumes.
The Geotechnical Enginneering Handbook probably has the answers to this, though I'm not sharp enough to decipher the techno-talk in the book. I can't get hyperlinks to work on HEF--the only clue I can give you is to do a Google Search for "Volume of Shot Rock", and look for the "Geotechnical Enginneering Handbook" link. If you can access this manual, browse the entire thing. I found some info on volume and hauling around page 471. Maybe another HEF member can decipher the handbook. The shot volume is going to depend on the type of rock and the various parameters used for the blasting, i.e. the depth of the holes, drill hole pattern and spacing, etc. which will affect the size (mix of sizes) of the shot rock. I'll ask my friend at the quarry next time I talk to him if there is a rough figure they use for the limestone quarry.
Also look at the Eng-Tips Forums Surface Mining: This book on Pipe and Excavation Contracting also touches on volumes of rock, though I don't know if answers your exact question. One of these books states that the shot-volume is roughly 50% more than the un-shot rock, but the Pipe and Excavating book points out that the size of the shot rock--too fine or too big--affects how much a bucket or truck will hold.
Thanks for the reply, How about bedrock or frost ripped by a dozer... 30% or something I wonder?
I think it's more like 80%. The little black calendar books that the Cat dealers hand out at the end of the year has it in it toward the back. Other handy formulas in there too.
Hi, Good solid granite will give about an 80% swell.
1 would have guessed 70%
There is a lot of variables. One of the biggest is how it is shot. If the pattern is too large, you end up with a lot of oversize, and that leaves many voids in a load, reducing the load volume when measured in bank yards. Another thing is the type of rock it is to start with. One other issue is the loads themselvs. I have seen many loader "operators" who put some rock on and send the truck away as "full" when it will hold another full bucket if it is placed right. If the truck is not heaped to the rating, your loads will always be lacking when the survey comes at payment time. There is no simple answer, and I have seen swell volumes in shot rock from 30% up to 150%++.
Here's a bit more info that may help or maybe give you some more variables.
Thanks Diggerop!