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Mike981
08-02-2008, 12:44 AM
I've lurked on this forum for awhile now and seemed to always find answers to my questions by just searing the forum but I was unable to find the answer on this.

I just got asked to bid on a job for a commercial building pad and the plans call for a 98% compaction. The cuts range from 4 foot and the fills from as little as one foot to 5 and a half foot over the pad. So my question is do you guys think that a sheepsfoot Vibratory roller will work for this? If not what would you guys recommend, and any tips on rolling pattern would greatly be appreciated.

The plan that I have in mind is to use an excavator to cut and a dozer to push the piles while another guy runs the roller compacting as the fill is brought up. But I'm not sure as this will be my first project with a compaction test, so any tips or ideas would be greatly appreciated.

JohnnyRoyale
08-02-2008, 12:46 AM
I would guess sheepsfoot for the fill, smooth drum for the granular. I may be wrong.

RockSet N' Grade
08-02-2008, 12:54 AM
I have built alot of commercial tilt-ups in my time from the ground up to finish and we always had to do what you are proposing. I would ask for a copy of the soils report to see what their test holes showed first. Understand that a soils engineer will determine when you find a suitable "bottom" regardless of what you bid, so use proper language in your bid to cover that. When we did our backfill/compaction we used a dozer and walked it with the dozer to get compaction. The native material and your choice of fill material will determine your success or failure of obtaining 98%. Get a copy of the soils report to see what was found and be clear in your contract/bid as to what is included and what is an extra. Make sure you have the soils engineer sign off on the bottom (not just a verbal "that looks like it will be ok thing")......

Gravel Rat
08-02-2008, 01:33 AM
You always let the engineer take the responsibility and let them tell you what they want done. I'am surprised they would allow native dirt to be used.

crab
08-02-2008, 09:23 AM
when ive done tennis courts they ask for the same and we used a10 ton vibratory roller,this i was told is the minimum you can use.

tbi
08-02-2008, 10:04 AM
I've lurked on this forum for awhile now and seemed to always find answers to my questions by just searing the forum but I was unable to find the answer on this.

I just got asked to bid on a job for a commercial building pad and the plans call for a 98% compaction. The cuts range from 4 foot and the fills from as little as one foot to 5 and a half foot over the pad. So my question is do you guys think that a sheepsfoot Vibratory roller will work for this? If not what would you guys recommend, and any tips on rolling pattern would greatly be appreciated.

The plan that I have in mind is to use an excavator to cut and a dozer to push the piles while another guy runs the roller compacting as the fill is brought up. But I'm not sure as this will be my first project with a compaction test, so any tips or ideas would be greatly appreciated.

Keep your lifts shallow, make sure your near optimum moisture and if the material changes that the tester has the correct proctor.

bobcat_ron
08-02-2008, 01:13 PM
Sheepsfoots are for dirt, they can be used for granular, but they shift the upper layer of material around to much, smooth drums are needed for compaction. I managed to compact a 4 foot lift of sand with a Cat 573 compactor to 102% compaction in 3 passes, 2 passes in low amplitude and the final in high amplitude.
We always use a packer that weighs at least 6 tons, that way our lifts can be 12" at a time, the heavier the compactor, the thicker the lifts, we also use manure tanks with fresh water and hammer and soak the sites down, even with out compaction, water will drop our sand levels 2 inches.

ksss
08-02-2008, 02:08 PM
Having the correct Proctor is really the key especially when using native material. It must be of such quality that they have a Proctor for that material type. Usually here they call for engineered fill, which is pitrun material, packs like a rock.


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Toy2
08-02-2008, 04:27 PM
I'm sure someone will or should do a density tests on what you do and give you direction on what steps are needed next.