Compacting Rock Screenings: Jumping jack or vibratory tamper?

[jcaron2]

I have a 5-6" (uncompacted) layer of rock screenings that I need to compact. Picture course sand that packs very tightly.

Anyone have any advice whether I should use a jumping jack type of tamper versus a vibratory one? I want it packed down really well.

Thanks.

 

[SPIKER]

I say it depends on side of area, large area plate compactor if small area or area with lots of stuff in way or narrow trench then JJ.
Mark

 

[powerstroke444e]

Jumping jacks are for dirt in trenches more often than not, plate compactors are for sand & gravel not for dirt. I would rent a plate compactor if you have room to run it, and with 6" you will need to go over it several times as they usually only compact about 3" deep. fyi if your doing large area like a driveway it may be cheaper to use a small roller.

 

[Egon]

Vibratory for granular materials.

 

[JB4310]

Jumping jacks as mentioned are for trenches, they work great for what they are designed for which is deeper compaction in a smaller foot print. It allows for higher lifts in between compacting. a time saver for back-filling.

In a slab construction you may only have a small amount to come up with fill, so the plate is made wider as it doesn't need to compact as deeply, hums right along leveling as it goes.

You go nuts with chasing around a JJ in anything wider than a 3-4 foot area.

jb

 

[jcaron2]

Jumping jacks as mentioned are for trenches, they work great for what they are designed for which is deeper compaction in a smaller foot print. It allows for higher lifts in between compacting. a time saver for back-filling.

In a slab construction you may only have a small amount to come up with fill, so the plate is made wider as it doesn't need to compact as deeply, hums right along leveling as it goes.

You go nuts with chasing around a JJ in anything wider than a 3-4 foot area.

jb

Thanks! That definitely answers my question. I've got five 12x12 horse stalls to do, so it sounds like the vibratory compactor is the way to go.

 

[flusher]

I have a 5-6" (uncompacted) layer of rock screenings that I need to compact. Picture course sand that packs very tightly.

Anyone have any advice whether I should use a jumping jack type of tamper versus a vibratory one? I want it packed down really well.

Thanks.

You need to work in 2" thick lifts, water the rock and then use a vibratory tamper. Repeat until you get the desired total thickness. That's the only way to get that gravel packed down really well.

I had my gravel driveway (20'W x 330'L x 6" thick) done that way in Jun05 and it's been maintenance-free so far.

 

[dcyrilc]

Thanks! That definitely answers my question. I've got five 12x12 horse stalls to do, so it sounds like the vibratory compactor is the way to go.

I just picked up on that it was for your stalls. Go for the plate compactor and do it in lifts as suggested. If possible, remove or rake back the sand and compact the dirt you put down first. Don't use water for the dirt. If I remember right, your dirt is a type of clay and sticks when wet. Compact the dirt in sections, then move the sand to where the dirt has been compacted so that you can compact the rest. After that, respread the sand and compact it. You can try it with or without the water for the sand.

Has the weather warmed up any. It will help if the grounds not frozen.

 

[dex3361]

I did my 300 foot driveway and also the area under my deck (10x46) in the type of gravel you describe. I used a vibratory plate because it gives a much better finish. I don't I agree that I would put it down in 2 lifts, keeping it damp but not soaked. When finished it will be very hard and last for years. Before putting the plate on it rake it out to the aproximate level you want and take off. It is not a bad job at all.

 

[dcyrilc]

I did my 300 foot driveway and also the area under my deck (10x46) in the type of gravel you describe. I used a vibratory plate because it gives a much better finish. I don't I agree that I would put it down in 2 lifts, keeping it damp but not soaked. When finished it will be very hard and last for years. Before putting the plate on it rake it out to the aproximate level you want and take off. It is not a bad job at all.

You're right that it will compact the 6", but he has 6-8" of loose clay dirt underneath that sand. I've used plate compactors at work for nearly 30 years and can tell you that he won't get the dirt compacted under the sand unless he does it first. The most penatration you can get with a plate compactor is about 6-8".