Bolts anchored in concrete 2

[lancealot72]

OK, i am not sure how to approach this problem. I dont have all of the details yet:

I have four 10" bolts anchored in concrete about 8" deep in a 5" square pattern. I will have a 1/2" steel plate with a 15 ft 4 1/2" sch. 40 pole welded to the center of the steel plate. Some minor equipment will be installed on top of this pole.

I am assuming that the bond from the concrete to the steel bolts is the weak link and if enought force is applied that it will rip the bolt from the concrete. I want to find out that max force. Some tip on what calculations to use and how to go about this would be appreciated.

thank you!

 

[chicopee]

swearingen- projected area of the pole is only .277 sq.ft., therefore how did you arrive at the 187.2 lbs of lateral force when I only got 9.24 lbs.?
Dimjim- I missed my typo error on the tension side of bolts; expression s/b 69.33*12/10=83.2 lbs.per bolt.
In so far as shear at the base it is not a significant value to determine resultant stresses.
The only thing missing is the projected area of the object on top of pole. Weight of top of pole also appear insignificant.
With regard to length of embedment on the tension side=
.04*.5*36000/(5000)^.5=10.2" per bolt. You may redo this calculation for different steels and concrete strengths. Also allow 3" clearance between concrete base bottom and ends of bolts.

 

[MikeHalloran]

Projected area of pole = 5.625 square feet.



Mike Halloran
Pembroke Pines, FL, USA

 

[WoodyPE]

Scorch said:

Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats.
--Howard Aiken, IBM engineer

Can I borrow your quote? Howard will be a famous man.

http://www.angelfire.com/planet/gadgetforum/index.html

 

[Scorch]

WoodyPE,

Feel free to the quote.

Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats.
--Howard Aiken, IBM engineer

 

[WoodyPE]

Thanks Scorch

http://www.angelfire.com/planet/gadgetforum/index.html

 

[WoodyPE]

you got a purple star from me. ;-)

http://www.angelfire.com/planet/gadgetforum/index.html

 

[Cockroach]

Bolt failure from concrete would be in shear. I've used 28 MPa concrete with a shear value of 57.7% normal. The wetted area of the bolting, i.e. that portion of the bolt in physical contact with the cement, would then easily give you an idea of loading resulting in failure.

My results have been pretty consistent with problems associated with anchoring shelving to warehouse floors, that sort of thing.

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada

 

[leDouche]

I hope you didn't need that pole up too soon. When in doubt, build a mock-up and see what you need to improve if it fails.
Interesting topic with great replies!