wall panel will be considered in computing the
transfer bending moments or diagonal tension across
minimum area of reinforcement. Joint reinforcement
the
joint:
joint
reinforcement
and
bars
in
used for crack control or mechanical bonding may be
nonstructural bond beams will be terminated at
considered as part of the total minimum horizontal
control joints.
Deformed bars in structural bond
reinforcement, but will not be used to resist computed
beams (those acting as chords and collectors) will be
stresses.
Further additional bars will be provided
made continuous for the length of the diaphragm
around openings, at corners, at anchored intersections
(refer to Figure 7-14).
in wall piers, and at ends of wall panels, as prescribed
elsewhere in this chapter. Vertical bars in walls will
(g) Design considerations.
be spliced as prescribed in ACI 530.
1. Wall weights. Refer to ACI 530 for
2. Reinforcing in shear walls. In special
the average weight of concrete masonry units and the
reinforced masonry shear walls, reinforcement
average weight of completed walls.
required to resist in-plane shear will be terminated
with a standard hook or with an extension of proper
2. Shearing stresses in hollow masonry
embedment length beyond the reinforcing at the end
shall be based on area of the grouted cores plus the
of the wall section. The hook or extension may be
minimum net bedded cross-sectional area of the
turned up, down, or horizontally. Provisions will be
members under consideration.
made not to obstruct grout placement.
Wall
reinforcement terminating in columns or beams will
3.
Boundary Zones.
When the
be fully anchored into these elements.
compressive strains in special reinforced concrete
shear walls exceed 0.0015 under combined loads,
3. Reinforcing in wall piers. Horizontal
boundary zones shall be provided as prescribed for
reinforcement will be in the form of ties as shown in
special reinforced concrete shear walls in Paragraph
Figure 7-16.
7-2f(3).
4. Column ties. For buildings in Seismic
(h) Reinforcing. Typical reinforcement is
Design Categories D, E, and F, the spacing of column
shown in Figure 7-16.
ties will not be more than 8 inches (203mm) for the
full height for columns stressed by tensile or
1. Minimum reinforcing. Unit masonry
compressive axial overturning forces due to the
must be reinforced not only for structural strength,
seismic loads of Chapter 3; and 8 inches (203mm) for
but to provide ductile properties and to hold it
the tops and bottoms of all other columns for a
together in the event of severe seismic disturbance.
distance of one-sixth of the clear column height, but
All walls and partitions will be reinforced as required
not less than 18 inches (457mm), nor
by structural calculations, but in no case with less
than the minimum area of steel and the maximum
spacing of bars prescribed in Chapter 11 of FEMA
302. Only reinforcement that is continuous in any
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