## Through-Bolt Design

## Through-Bolt Design

(OP)

Hi Gents,

I am trying to design a 300mm Diam. through-bolt which penetrates through 200mm THK reinforced concrete wall and it is under both axial and shear force. The checks that I am trying to apply are as follows:

1-Concrete bearing capacity ----> not sure how to calculate it for a through-bolt? what is the effective bearing length, I've to assume?

2-Punching shear (axial force in bolt generates a pull out force that tends to punch through wall)

3-shear capacity of bolt

I appreciate that if you can help me.

Regards,

Sam

I am trying to design a 300mm Diam. through-bolt which penetrates through 200mm THK reinforced concrete wall and it is under both axial and shear force. The checks that I am trying to apply are as follows:

1-Concrete bearing capacity ----> not sure how to calculate it for a through-bolt? what is the effective bearing length, I've to assume?

2-Punching shear (axial force in bolt generates a pull out force that tends to punch through wall)

3-shear capacity of bolt

I appreciate that if you can help me.

Regards,

Sam

## RE: Through-Bolt Design

Michael.

Timing has a lot to do with the outcome of a rain dance.

## RE: Through-Bolt Design

my apology, it was a typo. it should be 30 mm.

## RE: Through-Bolt Design

φV=φ*0.62*fyp*ns*Ap (Limit State Format)

where φ is the material reduction factor (0.9 for steel but refer to your steel code); fuf is the yield stress of the pin; ns is the number of shear planes and Ap is the cross-sectional area of the pin.

I think the design would be governed by one of the first two items.

## RE: Through-Bolt Design

asixth, does he need a special method for combining shear and tension in the bolt, as we used to do in working stress, or was that just friction bolts?.

Michael.

Timing has a lot to do with the outcome of a rain dance.

## RE: Through-Bolt Design

thanks for the comment. What code r u using?

paddingtongreen:

the main technical authorities would be ETAG001, Annex C, ETA-02/0042

But gents the main issue is defining the modes of failure. HILTI and other technical literatures discuss mainly about partially peneterated anchors (as attached), ACI for example specifically points out that the calcs do not cover through bolts. to my knowledge the modes of failure should be different between partially peneterated bolts and through-bolts.

what u reckon?

thanks

Sam

## RE: Through-Bolt Design

I seem to remember that there were diminishing returns on the shear cone with greater depths because of the bending of the rod. I thought you might find the limit in Hilti

Michael.

Timing has a lot to do with the outcome of a rain dance.