Question on Slip Critical connections.

[3doorsdwn]

I’m working on a bolted slip critical connection (using ASD 9th). I think I am following the procedure, but one thing eludes me: as far as I can tell, there doesn’t seem to be a provision in the code for pinching, wrinkling, tearing (or whatever you want to call it) stresses in the plate from the bolt bearing against it when it is pretensioned. You’d think there would be something. A foreign code I read addressed this by requiring the minimum thickness of the plate to be a (minimum) of one half the bolt diameter. Thoughts?

 

[csd72]

In my opinion, you can only really get an effective pretensioned joint when you have 2 plates in direct bearing against each other.

If there is a chance of buckling/ wrinkling then the bolt probably wouldnt reach full pretension anyway.

 

[UcfSE]

Try contacting the AISC steel solutions center. They are very responsive to questions sent to them.
Ask the Steel Solutions Center link

 

[VTPE]

AISC requires a hardened washer under the slip critical connection. This will address the issue of plate deformation. See the RCSC requirements for high strenght bolts. It is a free download on the AISC web site.

 

[271828]

You also will check bearing and tearout as if it was a bearing connection.

 

[henri2]

VTPE, according to AISC/RCSC provisions for HSBs, it seems that hardened washers are not always required in slip critical joints/connections. Ref: AISC 9th edition, page 5-272, item 7(c)....AISC 13th edition, pages 16.2-40&41, item 6.2.

 

[kelowna]

I never thought that could be an issue. The plates that the bolts connect must be very thin and you must have tension loads on them. I never heard about such a check, but then, I have done very little bolted splice design.
I would recommend you check

http://www.boltcouncil.org.

You can download for free the RCSC specification and the Guide Design Criteria for bolted and Riveted Joints. Those two documents have almost always provided the answers I was looking for.