Shear Walls With Openings - The Analysis of Irregular Shaped Structures - page 375

3. The nominal unit shear capacity for a single-sided wall shall not exceed 1740 plf
for seismic or 2435 plf for wind as given in Table 4.3A. The nominal unit shear
capacity for a double-sided wall shall not exceed 2435 plf for wind.

4. Where out-of-plane offsets occur, portions of the wall on each side of the offset
shall be considered as separate perforated shear walls.

5. Collectors (wall top plate, etc.) for shear transfer shall be provided through the
full length of the wall.

6. A perforated shear wall shall have uniform top of wall and bottom of wall ele-
vations, no vertical offsets. Perforated shear walls not having uniform plate
elevations shall be designed by other means.

7. The maximum wall height shall not exceed 20 ft.

Hold-downs are required to be installed at each end of the wall in accordance with
SDPWS Section 4.3.6.1.2, where

Vh
C i

TC == ∑ SDPWS Eq. 4.3-8

o

and

T = tension chord uplift force, lb

C = compression chord force, lb

V = total shear force in perforated shear wall, lb

h = wall height, ft

Σ L i = sum of lengths of full-height segments, ft

o = shear capacity adjustment factor from SDPWS Table 4.3.3.5, shown in Fig. 10.4.

If multiple studs are used for the chord members of the wall, the studs must be
fastened together to act as a single member to transfer the shear forces that the shear
wall is being designed for.
The unit shear force v max transferred into the top and bottom plates of a perforated
shear wall at full-height sheathed segments and into the collectors connecting the full-
height segments shall be calculated as follows:

V
C i

v = SDPWS Eq. 4.3-9

∑

max

o

where v max = unit shear force, plf
V = total shear force in perforated shear wall, lb
Σ L i = sum of lengths of full-height segments, ft
C o = shear capacity adjustment factor

A commonly overlooked component of a perforated shear wall is the aforemen-
tioned requirement for uplift anchorage of the bottom plate at the full-height segments.
Section 4.3.6.4.2.1 requires these anchors in addition to the hold-downs at the ends of
the wall. The uplift force for the additional anchors is equal to the unit shear v max times
the spacing of the anchors. Examples of uplift anchors can be seen in Fig. 10.2. The