Driving Timber Piles with Excavator Bucket
Driving Timber Piles with Excavator Bucket
(OP)
I am working with a contractor in a development who prefers to drive timber piling with the bucket of his excavotor. He has a Caterpillar 321C/LCR. It would be helpful to know what kind of energy he is imparting on the 12" by 25 foot timber pile. He typically drives the pile until he gets enough resistance to make his machine stand up. This is his "field test" I guess you could say.
If he is driving the piles with 3 to 5 foot swings with his bucket, could we come up with some magnitude of force this thing is imparting to help us arrive at a capacity figure for the pile? Any thoughts out there? Thank you for the interest.
If he is driving the piles with 3 to 5 foot swings with his bucket, could we come up with some magnitude of force this thing is imparting to help us arrive at a capacity figure for the pile? Any thoughts out there? Thank you for the interest.





RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
particularly those by PEinc and Panars
www.SlideRuleEra.net
RE: Driving Timber Piles with Excavator Bucket
Why is the owner letting him do this?! It's your job as the engineer to educate the owner about the risks that he may be required to assume by not requiring the Contractor to use a proper hammer. The excavator - and it's not really that big as DRC1 says - will impart lateral forces on the pile that may prejudice the development of skin friction after "driving" and/or damage the pile tip.
Jeff
RE: Driving Timber Piles with Excavator Bucket
I don't think my comments in the thread you referenced are relevant. That thread had to do with driving sheet piles with an excavator mounted vibratory hammer. This contractor isn't using any pile driving hammer; he's whacking the timber pile with the excavator bucket!
RE: Driving Timber Piles with Excavator Bucket
I do not believe that the referenced thread addressed sheet piling. The original poster said that the piles were 6" pipe piles. Both of our comments in that thread are applicable.
Good reference, SlideRuleEra.
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
You are right about the type of pile in the referenced thread; my mistake. I think your comment about load testing the pile with the excavator is appropriate to the current thread. However, I don't think my comment about doing a wave equation analysis applies to this thread. I don't know how you would figure out the energy from a dropping excavator bucket.
3of12 does not say what kind of soil the timber piles are being driven into. If the soil exhibits a lot of setup, this may be why this method has worked for the contractor in the past.
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
www.SlideRuleEra.net
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
The Contractor typically does this as is understood. Has there been problems with the buildings constructed so far or is it too early to say.
If I can place a pile to the desired depth by what ever means what is so wrong. Who care about the energy imparted to the pile. here I am confident of the soil stratigraphy below the pile base and I am also confident that there is no further settling layer below the base.
I think the Contractor has a bit more sense than we give him credit for. Let us think about it, he is driving through peat. There are soils in some parts of the world that it only takes the weight of the hammer resting on a wooden pile to send it down to the bearing layer. Buildings resting on those piles have survived well.
Who cares about the set and energy if we can get where we want. Intelligent pile design is first done through careful examination of the soil profile followed by what it takes to get the pile to the depth to which we want.
We are only designing for a two storey building. What is the fuss. How many piles is he using versus the load that will be transmitted to the foundation.
I think thatv you have a smart contractor for the given ground conditions
RE: Driving Timber Piles with Excavator Bucket
The original question was about how much energy was being applied to the piles during driving with the hoe bucket. So far, no one has answered that question.
RE: Driving Timber Piles with Excavator Bucket
I would check the depth of pile in the ground to determine if it has reached the sand layer. This can be readily done from the borings.
We must remember that pile design should not be undertaken by just looking at one approach. In the end we need to apply judgement to the information we obtain which should be based on observations as well as the use of the varied relationships that exist.
RE: Driving Timber Piles with Excavator Bucket
25' timber piles
15' of soft clay & peat
then 10' of sand
What is missing is how far did the contractor push the piles down? If it is to the sand (15'), then cutoff the excess pile length - I believe this is a real problem.
If it is the entire 25' (10' embodiment in the sand), perhaps your point is valid.
From my experiences as a bridge contractor, I expect the former case is more likely. If 3of12 can confirm the details, I'll offer my reasons.
www.SlideRuleEra.net
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
Good luck
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
RE: Driving Timber Piles with Excavator Bucket
http://youtube.com/watch?v=HJOoiIN5O7s
RE: Driving Timber Piles with Excavator Bucket
Now in reference to determining the load on the pile I think the the first response by DCR1 was right on point.