Page 155 - Handbook of Structural Steel Connection Design and Details

Design of Connections for Axial, Moment, and Shear Forces

140 Chapter Two

Figure 2.41 Bent plate. (Courtesy of Kloiber and Thornton,
with permission from ASCE.)

difficult to accurately fit and are expensive to fabricate. There are also
quality (safety) problems with plate cracking at the bend line as the
angle becomes more acute.
Single plates (Fig. 2.39) are the most versatile and economical skewed
connection with excellent dimensional control when using short slotted
holes. While capacity is limited, this is usually not a problem because
skewed members generally carry smaller tributary area. Single plates
o
o
can be utilized for intersection angles of 90 to 30 . Traditionally, snug-
tight bolts were preferred because they were more economical and
greatly simplified installation. However, the advantages of TC bolt instal-
lation often make it more economical to pretension the bolts, though,
since the bolts are not required to be pretensioned, no preinstallation
verification is required for these connections. Leaving the bolts snug-
tight can eliminate the “banging bolt” problem, which occurs in single
plate connections when pretensioned bolts slip into bearing. There are
AISC 13th Edition Manual (2005) tables available, which can be used
to select the required plate size and bolts along with the weld capacity
for the required load. This connection has an eccentricity related to the
parameter, a, of Fig. 2.39. The actual eccentricity depends on support
rigidity, hole type, and bolt installation. The actual weld detail, however,
has to be developed for the joint geometry. Welding details for skewed
joints were discussed in Sec. 1.3.7.
End plates (Fig. 2.40) designed for shear only are able to provide more
capacity than single plates and if horizontal slots are utilized with shug-
tight bolts in bearing some dimension adjustment is possible. Holes
gages can be adjusted to provide bolt access for more acute skews. A con-
structability problem can arise when there are opposing beams that

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