Design A connection 1

[Staed79]

How do i determine the nos on anchors needed if i have to bolt a C- channel on concrete.
I can have only one Bolt on the channel along the c/s
I know the moment at the base...
The thought process that is going on is to avoid the tripping of my bolt,
How much should be my embedment, i.e what is the min embedment i need to hold..
and how do i calculate my spacing of the bolts along the channel..
Guy's please help, i thanks all of you, for your advice..

 

[MiketheEngineer]

Size of C-Channel??
Loads - how much - what kind
Thickness of concrete - type - psi?
Size of anchors - what type

This should be fairly simple...

 

[msquared48]

If you are in the US and subject to OSHA regulations, you will need A 4 BOLT MINIMUM at the base anchorage to the foundation, whatever that is.

Maybe, just maybe you are lucky...

Mike McCann
McCann Engineering

 

[Lion06]

Mike-
I think you can get out of that 4 bolt minimum if your member qualifies as a post instead of a column. If it qualifies as a post, I believe you're only required to have 2 bolts.

 

[msquared48]

HMM... I didn't know that. Is this in the OSHA regs as an exception? How do they define "post" then as opposed to "column"? KL/r?

Mike McCann
McCann Engineering

 

[Lion06]

I am going from memory here, but a post is defined by height or load. Let me see if I can find the paper.

 

[Staed79]

Let me rephase my post:
I have a a unit which will hold glass.
this unit is bolted to concrete..
This unit ressembles like a channel , so mentioned it on mys posting
My max embedment depth is 3 1/2 " (not much)
my Moment will be some where 9 kip -in
breath of the unit is 1.5 inches, max size of the bolt will be 1"

i need to calulate, what spacing i should place my bolt,
[_] I can have 1 bolt on the c/s
|
my length of unit will be around 4-8 feet..
How should i go around calculating the required bolts..
thanks for the comments

 

[Lion06]

OK,
a post is defined as "a structural member with a longitudinal axis that is essentially vertical, that: 1.) is axially loaded and weighs less than 300#, or 2.) is not axially loaded, but is laterally restrained by the above member. Posts typically support stair landings, wall framing, mezzanines and other substructures."
A post is only required to have 2 anchor bolts, but must still resist teh 300# point load 18" from the face of the post.
This is apparently from some caselaw from January 18, 2001. The docket No. is S-775. It is approximately 58 pages, the uote I give above is on page 56

 

[nutte]

Mike/StrEIT, the post definitiion is in the OSHA code. Columns require 4 anchor bolts minimum. Posts are not columns, so they are not held to this requirement. I don't know of a 2-bolt minimum requirement for posts. It may be there, but I haven't come across it. See the links below.

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10787

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=12746

 

[nutte]

Also, I don't think posts are required to resist the 300# load 18" away. That is a column requirement, and posts are not columns.

 

[Staed79]

Are we moving away from the question, i know that imformation is also important.. ?
But please guy's please help out the question
"Let me rephase my post:
I have a a unit which will hold glass.
this unit is bolted to concrete..
This unit ressembles like a channel , so mentioned it on mys posting
My max embedment depth is 3 1/2 " (not much)
my Moment will be some where 9 kip -in
breath of the unit is 1.5 inches, max size of the bolt will be 1"

i need to calulate, what spacing i should place my bolt,
[_] I can have 1 bolt on the c/s
|
my length of unit will be around 4-8 feet..
How should i go around calculating the required bolts..
thanks for the comments"

 

[Staed79]

I am sorry for above posting, if i do't get my answers i will end up bald...and without finger nail on my right hand...

 

[mikesg]

Staed79, would you please clarify the scheme, I seem to miss something in the explanation.
From above discussion answers assume that your C element is vertical and you want a fixed connection to concrete for its bottom end. If so, aren't you allowed to have a plate and have whatever bolts are required?

But from what you have shown as a scheme it looks like your element is horizontal, lying on concrete surface with all of its length, and serves like a support for a vertical plate (the glass?) and you want it to act like a fixed support.

Mike

 

[FeSE]

How about scanning your drawings or a sketch. I would spend a lot more time thinking about this if you posted more details.

 

[Staed79]

Mike, your 2nd description is right. Channel
My C section is lying horizontal flat on the surface as [_]
Bolt ==> |
As Shown my Channel section need's to be fixed like a fixed support so that no overtunning take place ....
I can just put 1 bolt along the c/s as shown, but n number of bolts along the length..my channel section width (breath) is just 2"..the tricky question to me is how much embedment, and nos of bolts.
I know how to design in shear, and tension but how will one bolt along c/s restrict bending...

[_] ==> channel

| ==> Bolt (just one along c/s)

 

[Staed79]

Here is a rough sketch..