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Installing piles using a plate compactor 2

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noypeng

Structural
Jun 21, 2019
16
Is there a correlation between "impulse force" from a compactor specs used in installing the pile and the pile capacity?
 
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There maybe might be. However the energy imparted would be peanuts compared to a pile driving hammer.
 
If you can drive it with a plate compactor, either 1) it's a post, not a pile, or 2) you just wasted a perfectly good pile by dropping it in a swamp.
 
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It's a pile foundation for 3 log cabins. Pile diameter and embedment ranges from 4"-10" (sch 80) and 19' to 34', respectively. We were retained to provide engineered drawings after an inspector found out there were no permit drawings.
 
See attached pile logs. It says "refusal" but I don't know how to quantify the pile capacity. There is that possibility that there's a "mismatch" between the compactor, or not enough energy to drive the pile or less efficient\cy so you get early refusal.

 
Save yourself the embarrassment and ultimate failure of the 'piles' by using a hydraulic post driver, rather than attempting to use a plate compactor for something it was not made to do and isn't adequate to accomplish.
 
The piles are in the ground. The building sits on top of it already. If I were to start from scratch, I could have recommended driven pile or screw pile.
 
How did they install a 34’ pile with a track hoe? Something doesn’t seem right.
 
Consider reaching out to an pile instrumentation company. They may have some creative ideas or worse case the contractor has to go back and install some test piles to prove they work. I’m sure whatever they come up with will will cost your client some money but that’s typically what happens when you build before getting a permit.
 
MTNClimber, I have no clue how they did it. We were just provided with pile logs for us to check the pile. Unfortunately, it's getting common here now that people build without any permit, and only get engineered drawings when caught by authority.
 
noypeng said:
I have no clue how they did it (install 34' pile with a track hoe).

They were lucky... the plate compactor (model RHP 40V, per your attachment) crudely simulated a vibratory pile hammer. The soil just happened to respond to compactor's vibrations.

There is absolutely no correlation to a compactor's impulse force (or other specs) and pile capacity. Same is true for a "real" vibratory pile hammer.

[idea]
 
Yeah but how did they get the “hammer” on the pile head? The logs say seamless which I’m guessing it’s one 34’ length of pile? I would assume they would have to install them in 5-10’ segments like DIPs.
 
Any idea then on how to check the pile capacity based on the attached pile log other than a load test?

My supervisor just had a meeting with the contractor and he was told that the ground was pit run. Now I wonder how he was able to install the 4" pipe 27' into the ground without damaging it.
 
noypeng - All three of your attachments are for the model RHP 40V compactor that the pile log states was used. The track hoe is a separate machine, listed as a Hitachi 290 on the pile log. Suggest you meet with your supervisor.

[idea]
 
SlideRuleEra - In the first attachment "compactors.jpg", there's an inset photo of the compactor attached to the track hoe hence I put "not the exact model of the track hoe" in my previous email.
 
Under the circumstances I'd look at the cabin for how it sits. Check floor elevations, etc. If unacceptable differences are present, consider getting underneath and shimming the low areas and plan to come back in a year or two and do it again.

Edit: For doing the elevation survey use a garden hose filled with water and attach a clear tubing to each end. That way one can go into each room. Record the height of each meniscus above the floor to find elevation differences.
 
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