Pull out force calculation 1

[KelvinChung]

Hi,

I face some problem in my research..... can anyone provide the formula to calculate the pull out force required to pull the steel bar from concrete?

Thanks a lot.

 

[MiketheEngineer]

How big is the bar, how was it installed, what strength of concrete, etc, etc, etc................

And is this for school??

 

[KelvinChung]

It is 12mm deformed bar cast into a normal weight concrete with some grade.... i just wanna know if there any formula to calculate it because i cant get it anywhere.

This is for my own research.

 

[zelgar]

doing a quick google search on "concrete pull out formula"...

assuming a conical failure of the concrete at 45 degrees

Force = shear strength of concrete x pi x 1.4142 x H^2

where H is the depth of the steel bar.

Here's where I got the info:

http://mail.consulmar.es/documentacion/catalogos/chockfast/boletines/691B.pdf

 

[csd72]

Almondskidz, look in the concrete code under plain bar and you should find a formula.

The 45 degree formula given by zelgar is for headed anchor bolts and not necesarily applicable for plain bar.

 

[DWHA]

Have you looked in ACI?

 

[boo1]

see page 7 and 8 of attached Bond and Anchorage PDF

Un = 0.80*35*sqrt(fc?)= 28*sqrt(fc?)
Developement bond length (Ultimate)is ldu=Abfy/Un
ldu=.0357*Ab*fy/sqrt(f'c) for spacing of less than 6 inches
ldu=.029*Ab*fy/sqrt(f'c) for spacing of greater than 6 inches

Responsively
Boo1

 

[dik]

Can you re-post that article? I get a blank file...

thanks, Dik

 

[boo1]

see link

http://www.ce.memphis.edu/4135/PDF/Notes/Chap_10_1_Bond_&_Anchorage.pdf

 

[KelvinChung]

thanks for the information. I try if i can figure it out or not.