Replacing steel shims with high strength epoxy based grout - Steel bolted connection

[FE_struct1]

Hi all,

First post here. I'm working on a project where we're constructing a large bolted steel bracing system for a building (image link for steel connection below). Due to variability, it appears that the steel shims would require significant machining at site to allow proper fit. We're trying to get around it by looking at high strength epoxy based grouts but concerns have been raised about the grout creeping and reducing the pretension in the bolts. It's my first time considering things like this so I'd really love opinions/advice from the more experienced people here - would an epoxy grout with small diameter aggregates work in such a case irregardless of the creep ? Or should I be looking at other alternatives ?

Thanks in advance !

http://files.engineering.com/getfil...d0a-435b-832c-828f755c87ec&file=Capture_3.PNG

 

[thaidavid40]

Why are you having to machine shims for the "proper fit"? If this connection is carrying axial load, then the AISC Code of Standard Practice allows for quite a bit of angular and dimensional gap misfit. Are these members designated as AESS, and if so, what class?
Dave

Thaidavid

 

[XR250]

Seems like an odd place to use grout since I have only seen it used between steel and concrete or concrete and concrete.

 

[FE_struct1]

Why are you having to machine shims for the "proper fit"?

It's primarily because the steel assembly is to also carry several rather complicated 'expansion nodes' (can't share details without compromising confidentiality unfortunately). The nodes introduce installation uncertainties far greater than one would normally encounter and, based on past experience, the design consultants have recommended that a fair bit of shim machining may be expected.

After some googling, I've more or less given up on solely using grout as a shim substitute (creep not low enough/ service issues) and am instead looking at small central shim plates surrounded by grout. But it would be really great if anyone has any experience with using grouts in similar scenarios that they're willing to share.

 

[klaus.]

maybe this is of help
klick


best regards
Klaus