Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: Quick Help

[Subject Prev][Subject Next][Thread Prev][Thread Next]
If you have the W shapes in the field, you might want to consider welding a channel cap the same way you would if you were designing the support for a crane.

Regards, Harold Sprague


Date: Fri, 20 Nov 2009 05:28:50 -0800
From: gvshwnth(--nospam--at)
Subject: Re: Quick Help
To: spraguehope(--nospam--at); markajohn(--nospam--at)
CC: seaint(--nospam--at)

Thanks Mark and Harold for your quick response.
Yes,I inadvertently omitted to mention the span.
You both correctly guessed it as 25 feet from the BM value.
Threre is no horizontal brace to restrict the unsupported length of the compression flange.I  I later got the opportunity to do the calcs.
W8x18 is confirmed as being hopelessly inadequate.
However if the beam is somehow laterally held at mid third points , it will pass muster.
I checked this out later.
Without lateral support the smallest beam that I could suggest was W12x30.
This is in response to a quick query from the field. They have a W8x18 ready which they can support on walls and they need to lift 4000 pounds just once and they don't want to spend too much money.
I have noted Mark Johnson's point also alerting me to the need to prevent rotation at the ends of beam resting on the wall.
I am advising the field staff accordingly.
Thanks once again.

Hotmail: Trusted email with Microsoft's powerful SPAM protection. Sign up now.