Compaction Rollers - sheeps foot 1

[dfreise]

Is anyone aware of a standardized definition or description for compaction rollers?

Does the term sheepsfoot roller include rollers with numerous "pegs" longer than six inches welded or formed onto the drum surface?

Does the term sheepsfoot roller include rollers with numerous rectangular pads 4 to 6 iches high formed onto the drum surface?

Are the rollers described above for different purposes? Is one type just as good as the other when the purpose is to minimize permeability?

 

[dirtsqueezer]

Well, I'll tell you what I know. I believe sheepsfoot is a general term for rollers where your "pegs" have been welded to the drum at regular intervals. So far as I know, there is no standard design. If there are feet, it's called a sheepsfoot.

The general rule at my old company was to use sheepsfoot rollers for silt or clay, while using the smooth drum rollers for sand and gravel. I have seen sheepsfoot rollers used on gravel, but I don't believe they worked any better than the smooth drum. If you've got silts and clays, sheepsfoot rollers are definitely the way to go.

Cheers.

 

[SlideRuleEra]

Here is a link that may help

http://www.geoengineer.org/compact.htm

The name "sheepsfoot" is based on history, in ancient times (Roman Empire, I believe) a moving herd of sheep was found to be the best available way to compact soil for roads, buildings, etc.

As an aside, I am aware of a local contractor who seriously refers to a "small" sheepsfoot roller as a "lambsfoot" roller.

http://www.SlideRuleEra.net

 

[dfreise]

dirtsqueezer, For silts and clays, did your old company use the "peg" type as shown at the link SlideRuleEra provided or the "pad" foot type as shown at this link?

http://www.woltz.com/490/235.cfm

 

[BigH]

- then there is always elephant feet (the real ones!) - see Canadian Geo Journal article back in the 1960s!!

 

[dfreise]

Well I guess that would work if my site was in SE Asia instead of western Kansas, but then again the contractor might want a time extension if I spec'd elephant feet compaction! I wonder if a group of shillelagh wielding freshman would work?

Seriously though, If anyone has any background on sheeps foot rollers, styles and types and when to use one style or the other I would appreciate a reply. If you can give me any references/research papers on the subject (other than "this is the way we've always done it") I would be even more beholding.

 

[mitchell54]

dfreise,

Sheepsfoot compactors (pegs) are mainly used for tying in clay layers together...for instance when you are building a liner cap for a landfill and you need to place clay in lifts, inorder to tie the layers together you use a sheepsfoot. I have mainly seen these pulled behind a large dozer (Cat D8).

Padded foot compactors (the rectacngles) are also used in earth compaction (mainly clay) these are used more for when you need to pass compaction tests. They can also be used for sub-base.

Smooth drum compactors are for dry material compaction and used more for road base.

An additional thing is that there are also the vibratory compactors, padded and smooth. Great for when you know you are going to have compaction testing.

So in short if you are going for low perm. then sheepsfoot is the way to go, if you are looking for compaction then padded foot.

Hope that this helps, if you have more specifics I can assist further.