Influence of pile hammering on existing burieed utilites
Influence of pile hammering on existing burieed utilites
(OP)
Hello, Does anyone know any formulas that help in evaluating the potential of driving proccess of piles on adjacent buried steel pipelines. Pipelines are from 2 to 4 inches steel pipelines buried at 3 to 5 ft in very soft soil. The piling of the buliding are made of woood (8 to 12 inches)and they are far around 15 to 20 ft from the pipeline. I am using Attwell and Framer (1973) formula that requires pile energy per blow, empirical soil parameter, and source distance, to evaluate the Peak Particle Velocity (PPV). I used this formula for building before in combination with monitoring program.
But I cannot find in the codes ASME or Canadin the permissible value of PPV for undergraound utilitits
Any help or refernce to helpful materials concerning this subject is appreciated. Much appreciated.
But I cannot find in the codes ASME or Canadin the permissible value of PPV for undergraound utilitits
Any help or refernce to helpful materials concerning this subject is appreciated. Much appreciated.





RE: Influence of pile hammering on existing burieed utilites
RE: Influence of pile hammering on existing burieed utilites
RE: Influence of pile hammering on existing burieed utilites
The only thing you can do is
1) estimate the PPV generated by the rig which is to be used ( Ground Engineering published a good prediction tools for impact hammers in the 90's )
2) compare it to what is tolerated for structures submitted to mining blasting operations
Sensitive structures will admit at least a PPv of 5 mm/sec. if in doubt you can pre-drill a hole larger than the pile down to the level of the utility and then drive the pile. Vibrations induced to the utility will be reduced quite a lot.
RE: Influence of pile hammering on existing burieed utilites
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Influence of pile hammering on existing burieed utilites
"Sensitive structures will admit at least a PPv of 5 mm/sec"
is it at least or maximum
RE: Influence of pile hammering on existing burieed utilites
RE: Influence of pile hammering on existing burieed utilites
There are lots of data available on damage potential to building structures related to vibrations, whatever the source. In general, to prevent cosmetic damage to buildings, peak particle velocities (PPV) are limited to less than 0.5 inches per second (IPS).
A steel pipe, even with connections, is much more robust than the items on a building that would be subject to cosmetic damage. That is one of my reasons for my previous statement.
I have monitored vibrations numerous times from pile driving and other sources, checking for building damage during the vibration events.
Some soils attenuate damaging vibrations reasonably well. Yes, vibrations can occur that will damage buildings, foundations, underground utilities and other items in close proximity to the vibration source. This is particularly true of loose sands under buildings on shallow foundations, where even small vibrations can cause additional settlement and building damage. Not the same with a steel pipe, though.
At the distances you noted, and considering that you are using wood pilings (which will attenuate a lot of the vibration from driving and since wood pilings are not usually driven to refusal but to a pre-determined tip elevation, the vibrations don't usually increase much with driving depth), I would not expect damage to the pipe from this activity.
It is much better to monitor the vibrations during the event than it is to try and predict the vibrations by calculation. You are dealing with variable amplitude and frequency through a non-homogeneous material, so your calculable result is probably not much better than a wild-a$$ guess.
RE: Influence of pile hammering on existing burieed utilites
These things do not affect only mechanical things; it is typical after the local annual fair ("Fiestas del Pilar de Zaragoza") to have a number of appliances "toasted" by the imbalances caused to the electrical network to make place for the temporary displays. Total o partial casualties this year in the aftermath of these have been Digital TV box, DVD recorder, dishwasher and this same computer showing some BSODs (Blue Screen of Death) -never seen before- every 2 days or so.
RE: Influence of pile hammering on existing burieed utilites