hi Stress Engineer

i have doubt in blast load analysis. what u mean drag coefficient how i apply in blast load. my guess is there is no cd value for wind load factor. it only for wave load. In my analysis i am not considered a wave load cases.

what is shape factor? why we considere for wind case at 0.7?

"Drag" equations always involve a Cd (drag coefficient, shape factor) - it doesn't matter whether your looking at wind or wave. For pipes the value is typically between 0.55 and 0.7.

hi richard

explain in briefly? our client doc. they mention cd value 1.0. how i use? in caesar wind shape factor = 0.55 to 0.7, if i choose "wave" than only it will shows Cd work sheet. where i enter 1.0 as per our client comments.but my load case not mention wave conditions.

Kavin ,

I understand your question is, if Richard can briefly explain his answer.I don't think a brief answer will be enough for you. You need to work under an experienced engineer.

Pl. don't take my comments in a negative way.

Stress analysis is not about your ability to give input in CAESAR II.Pl. understand what you are doing.

Regards

You can use any coefficient you want, as aslong as you can justify it.

This ZIP file has data from two different sources:

Drag coeffiecent of a cylinder (pipe) is a function of Reynolds number. It is around 0.6 to 0.7 for wind loads, but for blast velocities it can be around 3.0

1 to 1.2 more likely.

And don't forget to multiply with the DLF. If your client specify a Cd=1, maybe can provide also this.

It is a realy difficult task to design for blast.

Good luck.