Not Using Anchor Reinforcement
Select design using or not using anchor reinforcement.
Using Anchor Reinforcement - anchor reinforcement strength is
used to replace concrete tension / shear breakout strength as per
ACI 318-11 Appendix D clause D.5.2.9 and D.6.2.9
Not Using Anchor Reinforcement - concretet strength is used to
resist concrete tension / shear breakout strength.
When Using Anchor Reinforcement option is chosen, it normally
significantly increases the anchor bolt capacity, but the code has
some specific requirements for rebar arrangement in order to be
considered being effective for resisting anchor tension and shear.
To take advantage of obtaining higher anchor bolt capacity by
using anchor reinforcement, the trade off is that the engineer has
to design and arrange the rebar around anchor bolt following
details in ACI 318-11 RD.5.2.9 and RD.6.2.9.
In the cases such as anchor bolts locating on a concrete pedestal
where the 4-side edge distances are very limited, or the anchor
bolt locating on a high seismic design zone, it would be very
difficult to get the anchor bolt design passed without using anchor
reinforcement. In these cases, uisng anchor reinforcement option
normally would be the only choice for anchor bolt design.
ACI 318-11 RD.5.2.9
To be considered being effective for resisting anchor tension,
vertical reinforcing bars shall be located within 0.5hef from
the outmost anchor's centerline.
ACI 318-11 RD.6.2.9
To be considered being effective for resisting anchor shear, hor.
reinft shall be located within min( 0.5c1, 0.3c2 ) from the
outmost anchor's centerline
