Relevant data from the table (Appendix B of textbook): Properties of Wide-Flange Sections (W shapes): U.S. Customary Units
Designation |
Web thickness |
W18 × 86 |
0.480 in |
W24 × 117 |
0.550 in |
Shearing strength of rivets:
There are 8 single-shear rivets in the girder and 4 double-shear (equivalent to 8 single-shear) in the beam, thus, the shear strength of rivets in girder and beam are equal.
$V = \tau A = 15 [ \, \frac{1}{4} \pi (\frac{7}{8})^2 (8) \, ]$
$V = 72.16 \, \text{ kips}$
Bearing strength on the girder:
The thickness of girder W24 × 117 is 0.550 inch while that of the angle clip L4 × 3-1/2 × 3/8 is 3/8 or 0.375 inch, thus, the critical in bearing is the clip.
$P = \sigma_b \, A_b = 32 [ \, \frac{7}{8}(0.375)(8) \, ]$
$P = 84 \, \text{ kips}$
Bearing strength on the beam:
The thickness of beam W18 × 86 is 0.480 inch while that of the clip angle is 2 × 0.375 = 0.75 inch (clip angles are on both sides of the beam), thus, the critical in bearing is the beam.
$P = \sigma_b \, A_b = 32 [ \, \frac{7}{8}(0.480)(4) \, ]$
$P = 53.76 \, \text{ kips}$
The allowable load on the connection is
$P = 53.76 \, \text{kips}$ answer