Base plate anchor rods 2

[JStructsteel]

So I am working on anchor rod design. Is there specifications on washer size for baseplates? Also, do you have to have 2 nuts(one under baseplate, one on top?

At the concrete end, I am just showing a nut jambed to the end of the thread. Does it have to have a washer? I know the design is based on diameter, do you folks use a washer? My detail so far.

 

[dik]

dvd... excellent article. I have a couple of comments:

Item 1: I always spec ASTM F1554 Grade 55 S1 so it's weldable. The strength increase since bolts use Fu is greater for little cost. Always weldable. Their Grade 36 is weldable without speccing it.

Item 10: I weld on the inside of the flange for the opposite side of the weld. They don't have to flip the column.

Item 12: Always...

Item 14: I never use Jam Nuts...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[JStructsteel]

Here is my detail I ended up with.

 

[dik]

I've been using headed anchor rods for over 20 years... They are far better than 'L' or 'J' bars... I still see the old bent bolts on most projects.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Eng16080]

JStructsteel, the detail looks good. One minor thing, you might want to show/note the threads extending to the "optional leveling nut." Be sure there's enough thread there accounting for a tolerance (like if they set the rod 1/2" too high).

 

[WesternJeb]

One more thing.. If you're using oversized holes then the plate washer needs to be welded to the base plate. Or else you have no form of shear transfer from the base plate to your anchor bolt. This gets left off a lot and contractors always want to cry about it where I am from.

edit: You will get friction due to bearing from the plate washer to the base plate.. But this is unpredictable and won't hold up for sufficient shear loading.

 

[Once20036]

I`m not a fan of including the "projection length".
It isn't engineering and the detailer can figure that one out.

WesternJeb - I agree for lateral columns only, but not every washer needs to be welded.

 

[WesternJeb]

I agree for lateral columns only, but not every washer needs to be welded.

Good distinction. My firm has taken the stance that it isn't worth the risk of letting this slip through the weeds so we have made it a standard for all columns. There are too many jobs with rushed schedules on both the engineering team and construction team to expect that amount of coordination to always take place perfectly. My apologies for not including that as a disclaimer .

 

[X4vier]

Consult, if I use "oversizes" holes per AISC 360 J3.3 table will need welded washers? or they can be omitted?

 

[X4vier]

Not omitted the washer but the welded washer!