Cylindrical pile under Lateral load- axisysmmetric condition 2

[jiligeo]

Is it possible to model a single cylindrical pile under lateral loads as an axisymmetric condition. Of course under vertical loads, the condition is axisymmetric but I am not sure about that under lateral loads.

Regards
Jalil

 

[rb1957]

are the lateral loads axi-symmetric ?

 

[jiligeo]

Hi rb, thanks a lot for your reply. The load is a point load at the center of pile and it is not axisymmetric.
I have confused because I have read the following sentence in a book:
“Unless the pile cross section is circular, the laterally loaded pile /soil system represents a three-dimensional problem.”

I think the model is 3D even for circular cross section.

 

[johnhors]

You do have one plane of symmetry, which you can take advantage of.

 

[rb1957]

if you've got an axisymmetric slice of the pile its seasy to copy that to make the whole pile (or 1/2 a pile using the symmetry in the plane of the lateral load).

personally, i think these "short cuts" are mostly irrelevent in todays world of massive memory and speedy machines.

 

[corus]

Some codes you can apply asymmetric loads to axisymmetric geometry. I think it's done by applying a fourier transform of the loads to the axisymmetric geometry and then summing the solutions. In some cases it's better to use axisymmetric geometry as you can have a very fine mesh in regions of interest rather than trying to use full 3D geometry and a large model. Saying that, you can also use a relative coarse 3D model and then sub-model any particular region with a fine mesh. Horses for courses I guess.

corus

 

[cbrn]

Hi,
Jiligeo, see the answer in the Ansys forum. I do suppose that, if you posted also there, you are using Ansys. Ansys is one of these codes which can handle non-axisymmetric loads on axisymmetric models, using "Harmonic elements" and, as Corus correctly says, an expression of the loads in terms of truncated Fourier series. You can express almost every kind of load distribution with this technique, however in general you won't need more than the first one or two terms of the Fourier series.

Regards

 

[jiligeo]

Dear friends, thanks a lot for your valuable replies, I guess the Harmonic elements are applicable only for linear models (geometry and material) as we use the principal of superposition.

Regards
Jalil