Re: Re: Design Pressure Including for Surge

From: <Christopher>
Date: Tue Aug 21 2007 - 11:19:00 EDT

On Aug 21, 2007, at 3:54 AM, blenrayaust wrote:

>

> Perhaps there is a need for more clarity and uniformity. I suspect the
> committee members on each of these standards are different with
> different points of view.

One particular difference is that Section VIII doesn't give you the 1.33 margin for incidental loads. Incidental loading like seismic and wind really have no explicit rules, but are covered by UG-22 and illustrated by some examples in Appendix L. You can't mix Codes, but you can get some guidance from the Nuclear Code on how to allow for upset conditions. Nuclear people have some serious safety considerations where systems need to be shut down in an orderly fashion if they can't remain operational in an emergency.

The dynamic loading is always tricky. The hooker is figuring out how to decouple systems for analysis so you don't have to do the whole plant just figure the stress in the door latch. For seismic loading you usually go from massive systems with subsystems taken as lumped masses. Accelerations on the lumped masses--taken as floor loading, for example, are used for detailed assessment of subsystems.

Christopher Wright P.E. |"They couldn't hit an elephant at chrisw@skypoint.com | this distance" (last words of Gen.

.......................................| John Sedgwick, Spotsylvania

1864)
http://www.skypoint.com/~chrisw/ Received on Tue Aug 21 11:19:00 2007