Densification in a Grid of Piles

[dlawrence529]

Hi,

I am trying to find a relationship between spacing of displacement piles and an increase in relative density/SPT value. I have not had much luck, other seeing that soils are densified for 3-5 (or other values depending on the source) pile diameters from the driven pile.

I am hoping to find one of those nice plots with a shotgun spray of data points and a straight line drawn through it. I am sure this could be turned turned into to a very complicated finite element model, but I am trying to avoid that if possible...

Attached is an illustration of what I am hoping to find

Thanks!

 

[dicksewerrat]

The next time you drive piles, drive to outside piles first. Then move in for the rest. Keep blow counts and travel for each blow on each pile. Then you should have enough info, including the original boring logs, to make some real good estimations.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[oldestguy]

Take a look at page 43 of "Civil Engineering" magazine, Sept 2015 edition. Interesting study that may assist. It may be on line also.

 

[BigHarvey]

Compaction piles is a ground improvement method. Depending on the type of soil and the volume displaced (grid size and diameter of pile), you can multiply the initial SPT values by a factor of 1.5 to 4 after treatment.