Page 94 - Handbook of Structural Steel Connection Design and Details

Design of Connections for Axial, Moment, and Shear Forces

Design of Connections for Axial, Moment, and Shear Forces 79

Figure 2.14c Free body diagrams for uniform force method.

and the column require the moments as shown to provide equilibrium.
For comparison, the free-body diagrams for the UFM are given in
Fig. 2.14c. These forces are always easy to obtain and no moments are
required in the beam or column to satisfy equilibrium.
From the unit force f 5.66 kips/in, the gusset-to-beam and gusset-
to-end plate weld sizes are D 5.66/(2 1.392) 2.03 sixteenths, actual
required size. For comparison, the gusset-to-beam weld for the UFM
would be
2
287 1 212 2
D 3 1.25 5 3.12
2 3 33 3 1.392
actual required size, a 54% increase over the L weld method weld of D
2.03. While the L weld method weld is very small, as expected with this
method, now consider the load paths through the rest of the connection.

Gusset to column.
7
Bolts. The bolts are A325N- / -in. diameter. with r 21.6 kips and r
8 v t
40.6 kips. The shear per bolt is 80/12 6.67 kips 21.6 kips, ok. The

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