Axial load - Pile

[kumaran856]

Can anyone provide me an approximate axial load than can be used to determine the structural capacity of a pile supporting a roadway signal post.

 

[csd72]

I would not think that the axial load would be an issue compared to the lateral bending.

I would think it would be so small that it could be ignored in the calculations.

 

[kumaran856]

Thanks for the reply. This is to determine structural capacity and not lateral capacity. The axial load affects the Nominal Moment capacity of the pile. Any suggestions?

 

[csd72]

You need to determine this yourself.

Otherwise analyse it as zero then analyse it as a conservative amount (say 10kips) then take the worst case.

 

[Bluefoot]

Collect the more accurate information from the owner and the selected supplier. They should provide you with the manufacturer's specs.

 

[Riggly]

I think that question is very vague, but I think you might be looking at a 25 to 30ft pole or so? I did some design for a few 30ft camera poles, and the axial force provided by the was about 1700lb, bending moment was about 10kip-ft, shear, 600lb, and torsion 45kip-ft. These numbers are site-specific (exposure factor, wind velocity, etc), dead load depends on type of material. What kind of pile are you looking at? However, said in the previous posts, loads will be neglible compared to the structural capacity of the pile. Your main concern should be lateral capacity as pointed out earlier, except if you are placing that pole in a swamp.

 

[kumaran856]

Riggly,

If axial load is negligible, how about torsion? How do we enter this in the L pile program? Can this be neglected too as piles can only designed for Lateral and Moment?

I do see the 45 kip-ft (significant) number for your design.

 

[csd72]

The torsion is taken out by interface friction around the circumference of the pile. A pretty simple hand calculation.

 

[16adams]

I am putting together a building foundation report and had chosen drilled shafts but the new loads are over 900 kips and the shafts are so large in diameter that they nearly touch. FHWA and others suggest a minimum spacing of 3 diameters. Has anyone put them closer together? I need them to be around 9 ft center to center because of the structure above. They are unable to change the column locations.

 

[BigH]

16adams - you should start another thread with this question - "hijacking" a thread not the best thing to do. In the 'pane' listing all the threads - go to the bottom and copy your post above in it. Submit it and perhaps we'll respond.

 

[mudman54]

you should be able to find loads in
Minimum Design Loads for Buildings and Other Structures, ASCE/SEI 7-0