Allowable Lateral Deflection of Timber Piles 3

[zero1238]

I inspected a home built on 12" timber butt piles today where the piles extended roughly 7'-4" above grade. My client was concerned about 2 piles specifically which appeared to be skewed and when I placed my level on them, this assumption was confirmed. The tops of these two piles were leaning about 3" (over my 48" level) towards the underside of the house. I'm trying to find allowable deflection criteria in the codebooks but can't seem to locate anything. Can anyone shed some light on this or point me in the right direction? Thank you.

 

[SlideRuleEra]

During pile driving, alignment tolerance of 1/4" per foot of pile length is a common requirement. Here is the appropriate excerpt from the South Carolina DOT Standard Specification:

http://www.SlideRuleEra.net

 

[Settingsun]

4% in this code for a pile before applying load.

https://up.codes/viewer/new_york_ci...014/chapter/18/soils-and-foundations#1808.6.1

Sounds like you may have some contribution from load though, and maybe creep.

 

[zero1238]

Thank you for your replies, this definitely helps to clarify it. Sounds like 6" over the entire height is too excessive to not recommend a repair.

 

[SlideRuleEra]

Sounds like 6" over the entire height is too excessive to not recommend a repair.

Don't be too hasty. Loading on typical residential piling is very low compared to the capacity of a driven pile that size. Even if attempts to realign the pile (above it's point of fixity) are successful, there will likely be damage. That damage would probably be unseen, below ground level.

I suggest making a reasonable estimate of loading and look at how that pile interacts with surrounding piling. Actually "doing something" would be a absolute last resort, and only if there is clear evidence that the pile's batter is causing problems.

http://www.SlideRuleEra.net

 

[zero1238]

I'd prefer not to modify it if I didn't have to but there was a diagonal crack above the doorway and it is currently over double the acceptable battered limit.

 

[Bobby46]

I've seen plenty of timber piles that have a localized "sweep". This can look concerning when only the sweep is projecting out of the ground. It is entirely possible that pile is plumb below the ground surface

It is also entirely possible that the other piles that appear plumb are not plumb below the ground surface. The appearance of a sweep projecting above the ground can also give the pile a favorable appearance.

The natural taper of the pile may also affect your batter measurement of 3" over 48"

If the framing of the house can sit on the pile, I would not worry about it.

 

[zero1238]

Thank you for all of the replies, these were extremely helpful.