CSP as a structural member
CSP as a structural member
(OP)
I'm a junior water guy -- does anyone have experience calculating failure modes of CSP as a structural member? I'm using CSP to protect/support a watermain across a bridge with piers spaced 4m apart. I wish to verify deflection in that span, and yield condition.
Do I use wl^2/8 for max moment and 5wl^4/384EI for deflection? Then how do I get my ultimate values?
Thanks,
Stan
Do I use wl^2/8 for max moment and 5wl^4/384EI for deflection? Then how do I get my ultimate values?
Thanks,
Stan






RE: CSP as a structural member
RE: CSP as a structural member
The CSP I'd like to use is found at:
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They give a moment of inertia, I'm just not confident in the process of calculation (Ultimate/Allowed).
RE: CSP as a structural member
http
www.SlideRuleEra.net
RE: CSP as a structural member
http://www.ncspa.org/shop.asp
www.SlideRuleEra.net
RE: CSP as a structural member
Ultimate loads are a little tougher since you need Zx or the plastic section modulus. This value is derived through integration.
I would suggest a service check as they are normally more conservative.
RE: CSP as a structural member
RE: CSP as a structural member
RE: CSP as a structural member
There is always finite element analysis but I doubt you are wanting to put that kind of time in.
RE: CSP as a structural member
If you calculated the bending due to the eccentricity of the corrugations you would find this would be excessive, and that the pipe would fail at almost no load at all.
Have you ever seen those straws that bend at half way down their length? The only difference between the straight and the bendy bits is that the bendy bits have corrugations!
RE: CSP as a structural member
RE: CSP as a structural member
The supplier gives a moment of inertia in mm^4/mm, which I'm told is called the pipe wall moment of inertia. I'm additionally unclear of how to use this type of inertia (how to get just mm^4).
Thanks to all for responses.
RE: CSP as a structural member
How about using a circular hollow section as the actual water main?