Percentage of Hor. Tie Bar Developing Full Yield Strength
This is a parameter used in anchor reinforcement shear breakout
resistance check.
When using hor. tie bar to resist shear breakout,
at nodes where
hook is located the tie bar cannot develop full yield
strength.
The following two assumptions are made for the anchor
reinforcement shear resistance calculation.
1. Use the pullout
resistance in tension of a single hooked bolt as
per ACI318-11 D.5.3.5 Eq. (D-15) as the max force can be
developed at hook T
h2. Assume 50% of hor. tie bars can develop full yield
strength T
r , the rest 50% can only develop
pullout resistance at hook T
h If user agrees with above
assumptions, user can select
50% hor.
tie bars develop full yield
strength option, as a result of this
option more hor. tie bar
(more legs, bigger bar diameter) may be
required to provide adequate
shear breakout resistance.
There are cases where the hook reduction
is not applicable.
For example, when the hor. hair pin is used and
adequate
development length is provided at both side of breakout line,
user
can select
100% hor. tie bars develop full yield strength
option in these cases.