30 November 1998
c. Column Bending and Composite Behavior. The shear panel anchor guidance will provide
moment resistance at the column ends, especially when no axial load is applied to the columns. The
columns built up from studs must be designed to act as a composite cross-section. Table D-10 gives
the intermittent weld length, L (2 inches for each built-up column in Table D-10) and maximum center-
to-center intermittent weld spacing, smax needed to ensure composite behavior of the columns. This
is based on Equation 3-9. Based on the values of smax given in Table D-10, actual weld spacing is
selected that round down to the nearest full inch from the values given in Table D-10. These welds
are made between all studs in the column and begin at both ends of the columns.
d. Column Combined Axial and Moment Capacity. The combination of axial and bending
load is evaluated for each trial shear panel. For each case, an interaction value is determined
according to Equation 3-10. Table D-10 shows that the interaction values, I fall below 1.0 for all
columns in this example.
Table D-10. Column Intermittent Weld Design, and Combined Axial and Moment Capacity.
Distance Mom of Weld Intermittent
Column 1 Side of to Neutral Column Shear/ Weld Max o.c. Max Yield Lat Defl
Moment Nominal Interaction
at Strap @ δymax Moment
Shear Crit Weld
Length Length Spacing
e. Column Shear Capacity. The column design shear capacity, VC is calculated according
Equation C-46 for each trial column. The values are shown in the second column of Table D-11.
These are below the strap maximum estimated ultimate lateral capacity (Phumax = Ω 0QE) calculated
according to Equation 3-24, with values given in the third column of Table D-11. Therefore, the
additional shear capacity from anchors is needed to resist the maximum lateral force, as shown in
D11. DIAGONAL STRAP-TO-COLUMN CONNECTIONS. Diagonal strap-to-column connections are
designed to resist the maximum estimated ultimate force in the strap, Psu defined by Equation 3-15.
Values of Psu are given in the second column of Table D-12 for each panel.
a. Screwed Fastener Connection Design. All screws used in this example are #10 self-
tapping hex head screws, as this is the largest practical size that will not interfere with drywall
installation. The nominal screw diameter, d for #10 screws is 0.190 inches.10 The following fastener
layout guidance is based on the Screwed Fastener Connection Design guidance in Chapter 3,
AISI Specification Commentary, Table C-E4-1.