×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Franki Pile Design

Franki Pile Design

Franki Pile Design

(OP)
Ok, I've done several searches on this site over the last four years for Franki pile design and have always returned empty handed.

Every once in a while, in my travels, I come across a site that would be ideal for Franki piles.........a very competant bearing strata located approximately 35 to 40 feet below ground surface with the upper strata very soft, saturated and provides little or no skin frictional contribution for pile capacity.  Footings are a waste due to excess settlement and groundwater infiltration.....etc.....etc.

Usually in these situations we recommend driven piles (steel or timber)....but just once I would like to do a franki pile comparison as there are times when extending pile length due to welding and splicing is quite time consuming and expensive.

Does anyone have a really good reference for franki pile design?  Building and designing the bulb as well as the complext shaft resistance components.

Thanks in advance and Happy New Year

 

RE: Franki Pile Design

Franki is a big international piling company and these days does lots of different types of piles.  But I assume by your post you mean cast in place expanded base piles which they call Frankipiles.

In my experience, you need to involve Franki for selection of the pile type, and the design, installation, and certification is by Franki.  That is the way it has worked on projects I have been involved in.

RE: Franki Pile Design

(OP)
hokie66,

Thanks for your comments.  You are correct, that they are expanded base piles, but not to be confused with belled piles.  These are cased and the pile consists of a gravel and portland cement mixture.  

There has got to be some design data out there for this..........I have seen AMEC design these before, so I am sure the information is out there......just getting my hands on it seems to be the tricky part.

RE: Franki Pile Design

(OP)
Thanks PSlem

RE: Franki Pile Design

I have a paper by Rey Nordlund delivered at Lehigh University in 1970, in which he presents the dynamic formula used by Franki to install the PIFs.  It does not present a static design approach.  His paper includes references to papers by Demcsak 1968, Meyerhoff 1959 and 1960, and O'Neill 1963.  I can send you a copy if you wish.

I believe the approach was mostly art for a long time, based on the thickness and density of the bearing layer and how well the soil was expected to densify during compaction of the bulb.  Franki would look at the boring logs, suggest a capacity, and back it with their performance bond.  I haven't dealt with Franki for a long time, but my first thought would be to give them a call.

 

RE: Franki Pile Design

I've seen papers - in the past (early DFI papers??) that detail the design of "expanded base piles" (which might be a better search than Franki piles.  They have "capacity" vs volume of concrete extruded. Sorry, am on vacation and have nothing in front of me to be more specific.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources