Civil Engineering Reference
In-Depth Information
M
e
S
bt
A
b
=+
300
30.0
(
0.6
)
=
σ
bt
=
16.67 ksi for top bolts
≤
44.0 ksi OK
M
e
S
bt
A
b
=+
300
60.0
(
0.6
)
=
σ
bt
=
8.33 for the second row bolts
T
bt
= σ
bt
A
b
=
16.67
(
0.6
)
=
10.0 kips for top bolts
T
bt
= σ
bt
A
b
=
8.33
(
0.6
)
=
5.0 kips for top bolts
Prying action (Equation 9.38):
10.0
3
b
10.0
3
(
2.25
(t
p
)
3
20
(
0.5
)
3
20
−
0.25
−
.05
)
T
Q
=
8
a
−
=
−
8
(
3.75
)
=
0.14
(
10.0
)
=
1.4 kips for the top row bolts
5.0
3
b
5.0
3
(
4.00
)
(t
p
)
3
20
(
0.5
)
3
20
T
Q
=
8
a
−
=
8
(
1.25
)
−
=
1.19
(
5.0
)
=
6.0 kips for the second row bolts
Tension in top bolts
=
T
b
=
10.0
+
1.4
=
11.4 kips
Tension in the second row bolts
=
T
b
=
5.0
+
6.0
=
11.0 kips
Shear stress on the bolts:
P
n
s
n
b
A
b
=
70
10
(
0.60
)(
1
)
=
τ =
11.67 ksi
Combined shear and tension
1
T
b
T
bP
17
1
11.4
39
f
bv
f
bv
=
−
=
−
=
12.0 ksi
≥
11.67 ksi OK
check bearing stress
70
10
(
0.50
)(
1.00
)
=
σ
bc
=
14.0
≤
f
B
ksi
l
e
F
u
2
d
b
=
(
1.5
)(
65
)
2
(
7
/
8
)
f
B
=
≤
55.7 ksi,
assuming a minimum loaded direction edge distance of 1.5 in., OK
or
f
B
=
1.2
F
u
=
1.2
(
65
)
≤
78 ksi
Shear and torsion on bolts in Side Elevation:
The direct shear stress,
t
, in the bolts is
P
n
s
n
b
A
b
=
70
(
2
)
8
(
0.60
)
=
τ =
7.3 ksi
