Concrete Embedded Lifting Anchor Design

[umrce]

I am designing an embed for picking a precast panel. Could someone please help clarify if I am ok to design this with LRFD factors or am I required to use OSHA's minimum 5:1 (or is it 4:1) FOS? I know OSHA applies to rigging, fall protection, etc., but does it apply to the design of my lifting anchorage?

Thanks

-R

 

[MiketheEngineer]

Only if you are standing underneath it....

 

[umrce]

Well played sir, well played...

 

[ishvaaag]

The CPCI (Canadian Precast/Prestressed Concrete Institute) 4th Ed Manual gives the safety factors for temporary conditions, that are not as high, but in far more ordinary level. It has also detailed info on much of what ongoing with precast parts, handling and erection included.

However it is pertinent that these "ordinary" and optimized safety factors need be combined with accurate design as proper of industrial work, to be repeated a lot of times. Careless design/construction of insets, eyelets, cables on these safety factors may signify disgusting surprises. So when designing these items circumstantially be very cautious, preferably following applicable example or guide from expert people.

 

[Duwe6]

It's 4:1 for OSHA "withstand 5x design load" so failure is acceptable at 5.1 x load. I would not go below 3:1 [should be the LRFD factor] without performing NDT on the actual steel being embeded, and personally signing the Pour-Card as the rebar inspector. The lugs may only get used once, but it gets pretty exciting when lugs fail.

Seen it happen several times on tilt-up slabs. Lug design was 'off' and the concrete company cast them just like the engineer drew them.