Spiralweld Pipe Failure Criteria

[DWHA]

I was wondering in anyone has come across a failure criteria that is common or specific to spiralweld pipe. I am working with a client that would like to use some spiralweld pipe on a project as piling. I have thought about it and I cannot think any reason that the spiralweld pipe would not be able to be designed the same way that any round section would be. But I thought that I would post here to see what others think.

Thanks in advance.

 

[BarryEng]

I do not know of any specific failures attributed to spiral weld pipe. It has been used in my area since 1986, mostly in retic pressures but some 1,500 mm pipe has been used to over 300 m head (11 plate).

Spiral weld pipe has also been used for piling since the above date.

Have a look at AWWA M11 (American Water Works Assoc Manual M11, steel pipe design & installation) - make sure that you use the 2004 (4th) edition & not earlier editions due to some typos.

Page 18 has a section of 'evaluation of stresses in spiral welded pipe'.

sigma = sigma(1) (cos^^2(alpha) + sigma(2) (sin^^2(alpha)

sigma = stress normal to pipe axis
sigma(1) = long. stress parallel to pipe long. axis
sigma(2) = hoop stress in pipe
alpha = angle of spiral weld seam relative to the long. pipe axis

You can also google 'American Spiral Weld Pipe' but they don't appear to reference stresses on the spiral weld. They appear to have started production in 2000.