Building Design and Construction Handbook - Merritt - Ventech!

8.38 SECTION EIGHT
TABLE 8.11 Nominal Tension Stress, F�nt (ksi), for Bolts Subject to the Combination of
Shear and Tension
Description of bolts
Threads not excluded
from shear planes
Threads excluded
from shear planes
Factor
of safety �
A325 bolts 110 � 3.6ƒ v � 90 110 � 2.8ƒ v � 90 2.0
A354 Grade BD bolts 122 � 3.6ƒ v � 101 122 � 2.8ƒ v � 101
A449 bolts 100 � 3.6ƒ v � 81 100 � 2.8ƒ v � 81
A490 bolts 136 � 3.6ƒ v � 112.5 136 � 2.8ƒ v � 112.5
A307 bolts, Grade A
When 1 ⁄4 in � d � 1 ⁄2 in
When d � 1 ⁄2 in
The shear stress, ƒ v, shall also satisfy Table 8.10.
52 � 4ƒ v � 40.5
58.5 � 4ƒ v � 45
FIGURE 8.11 Bolted connections with two bolts.
Case 2 of Fig. 8.11 has the two bolts, with 4-in spacing, arranged in a single
line along the direction of applied force. For the top sheet (Fig. 8.11) at section 1-
1 then, r � (T/2)/T � 1 ⁄2, and for this sheet at section 2-2, r � (T/2)/(T/2) � 1.
For the top sheet at both sections, d/s � 5 ⁄8/4 � 0.156.
From Eq. (8.45), for the top sheet at section 1-1,
1 1
Ft � (1 � 0.9 � ⁄2 � 3 � ⁄2 � 0.156)Fu � 0.784 Fu
The maximum load for that sheet would then be
11 3
Pn � [4 � ⁄16] � ⁄16 � 0.784 � 48 � 23.37 kips
For section 2-2, top sheet,
F � (1 � 0.9 � 1 � 3 � 1 � 0.156)F � 0.568F
t u u
Maximum load for section 2-2, top sheet, would then be
2.25