I have seen that PV Elite only check the anchor bolts under tensile stress and do not perform a check under shear stress or under combined tensile & shear stress.

Can you please let me know why it is so?

Regards,

Hrushi

Hello Hrushikesh

The shear stress in the bolt is very small. Being a friction grip system, the friction between the base (foot) plate and the concrete is very high because of the tension in the bolt. The shear stress is really inconsequential.

Do you feel strongly that the shear stress should be considered? How would you suggest we combine the shear and tensile stresses which are at right angles to each other?

Hi Ray,

Although shear stress component is less, it matters when tensile stress is close to allowable. I can send you an excel sheet how this tensile stress can be combined with shear stress. Please let me know your e-mail address.

Regards,

Hrushi

Dear Hrushi,

Just to add some something, the ASME Sec. Div. 1 allowable for bolts are conservative. In the structural field the anchor bolts have tensile allowable and shear allowable. With shear allowable being less.

But, ASME Sec. VIII Div. 1 provides one allowable for the bolts and that seems to be smaller than shear allowable used in the structural engineering. I think I compared SA-307.

So, look at the allowables that you are using too. You may be getting some inherent conservatism using ASME allowables.

I agree with Ray that friction is considerable, this is also mentioned in many engineering handbooks dealing with anchor bolt design.