Using Anchor Reinforcement or
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
CSA A23.3-14 Annex D clause D.6.2.9 and D.7.2.9
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 CSA A23.3-14 Figure D.10 and
Figure D.17B.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.
CSA A23.3-14 Figure D.10To be considered being effective
for resisting anchor tension,
vertical reinforcing bars shall be located
within 0.5h
ef from
the outmost anchor's centerline.
CSA A23.3-14 Figure D.17B
To be considered being
effective for resisting anchor shear, hor.
reinft shall be located
within min( 0.5c
1, 0.3c
2 ) from the
outmost
anchor's centerline