96
9-1
Prob. 9.2
= P/A
————————————————————–
__
Prob. 9.3
AB: A = 4 in.2
__
Prob. 9.4
P = 70 kN = 70 ×103 N
(a) A = 25(50) = 1250 mm2
————————————————————–
__
Prob. 9.5
(a) psi 4000
4
000,16
t
(b) psi 4178
83.3
000,16
t
————————————————————–
Prob. 9.6
Segment A:
Prob. 9.7
Total load = 16,000 lb
—————————————————————
Prob. 9.8
2
in. 75.1
000,35
dReq’
P
A
Use a 1½  diam. rod
—————————————————————
Prob. 9.9
Prob. 9.10
AB = shear area per bolt
AB = 0.7854(0.875)2 = 0.6013 in.2
lb 440,17
)6013.0)(2(500,14
(all) B
AP
—————————————————————
Prob. 9.11
A = shear area
A = dt = (1)(0.5) = 1.571 in.2
97
Prob. 9.12 (cont.)
(b)
A = dt = (0.75)(0.375) = 0.8836 in.2
—————————————————————
Prob. 9.14
(a) in./in. 0010.0
)12(100
2.1
L
—————————————————————
Prob. 9.15
in./in. 01875.0
8
85.78
L
—————————————————————
Prob. 9.16
Total elongation = 0.80 in.
—————————————————————
Prob. 9.17
in. 0125.0
000,000,30
)5.2(000,15
E
L
AE
PL
—————————————————————
Prob. 9.18 E = 30,000 ksi
Prob. 9.19 E = 70×103 MPa
MPa 4.132
491
1065 3
A
P
(b) 3
31089.1
4.132
s
Prob. 9.20
)000,000,30(442.0
Segment 2:
A = 0.7854(0.50)2 = 0.1963 in.2
in. 0509.0
)000,000,30(1963.0
)12)(5(5000
2AE
PL
Total = 1 + 2 = 0.0735 in.
—————————————————————
Prob. 9.21 (P.L. = 125 ksi)
98
9-3
Prob. 9.26
(a) Comp. stress in diagonal:
MPa 889.0
150
1020
2
3
A
P
c
—————————————————————
Prob. 9.27 Refer to Appendix G.
—————————————————————
Prob. 9.28 P = 60 k
—————————————————————
Prob. 9.29
ft 90.424 side dReq’
ft 24
5.2
60
dReq’ 2
(all)p
P
A
Use a square footing: 5-0x5-0
—————————————————————
Prob. 9.30
Prob. 9.31
A = 25(100) = 2500 mm2
t(all) = 140 MPa = 140 N/mm2
P(all) = A t(all) = 2500(140)
= 350,000 N = 350 kN
lb/ft09396.0
1728
Total wire wt. = 0.09396(400) = 37.58 lb
58.37
P
tf = 0.515 in.
tw = 0.295 in.
ksi 56.19
71.9
190
n
tA
P
—————————————————————
P = 7(10.5×103) = 73.5×103 N
2
3
(all)
mm 525
140
105.73
dReq’
t
P
A
mm 9.25
7854.0
525
dReq’ d
99
9-4
Prob. 9.35
P = 20 k, L = 30 ft, (limit) = 0.25 in.
t(all) = 24 ksi
Use a 1 1/8  rod
—————————————————————
Prob. 9.36 (2 bolts)
Ab = bolt cross-sectional area
—————————————————————
Prob. 9.37
—————————————————————
Prob. 9.38
Washer: I.D. = 27 mm, O.D. = 64 mm
t = 5 mm
Resisting shear area:
Prob. 9.39
A = d t = (0.75)(0.5) = 1.178 in.2
psi 930,50
000,60
P
Prob. 9.41 P = Force (lb) acting on key
Mo :
0.5P = 60(12)
P= 1440 lb
Width of key b:
A = b×length
Reqd b = 0.36/1.5 = 0.24 in.
Use ¼ width
—————————————————————
Prob. 9.42
1070
E
mm 85.5
)1000)(3)(1095.1( (c) 3
L
—————————————————————
Prob. 9.43
100
Prob. 9.43 (cont.)
(b) 000418.0
000,700,1
710
E
in. 0426.0
)12)(5.8)(000418.0( (c) L
—————————————————————
Prob. 9.45
A = cross-sectional area
= 0.7854(1.25)2 = 1.227 in.2
—————————————————————
Prob. 9.46
—————————————————————
Prob. 9.47
= 45 mm, d = 5 mm,
A = 0.7854(5)2 = 19.64 mm2
L = 18 m = 18×103 mm
E = 207,000 MPa
N1016.10
1018
)000207)(64.19(45
3
3
L
AE
P
MPa 517
64.19
1016.10 3
A
P
t
)000,000,30(10.0
)12)(20(000,30
dReq’ (b)
2
E
PL
A
psi 800,20
40.2
000,50
(b)
A
P
t
—————————————————————
Prob. 9.50
A = 0.7854(0.75)2 = 0.442 in.2
(more)
101
9-6
Prob. 9.50 (cont.)
—————————————————————
-Prob. 9.51
FV = +80  100 + CD(4/5) = 0
CD = +25 k (comp.)
Prob. 9.52
Section Load
(lb; tens.)
L
(in.)
(in.)
= 6000/0.25 = 24,000 psi < 34,000 psi OK
—————————————————————
Prob. 9.53
A = 0.25 in.2; E = 30,000,000 psi
A 6000 (T) 72 +0.0576
B 8000 (C) 48 0.0512
C 4000 (T) 24 +0.0128
Total = +0.0192
(elongation)
Check max. stress level:
= 8000/0.25 = 32,000 psi < 34,000 psi OK
—————————————————————
Prob. 9.54
102
9-7
Prob. 9.54 (cont.)
BC = 96.0 kN (tens.)
AC = 76.5 kN (comp.)
—————————————————————
Prob. 9.55
FV = 2 (0.7071T )  2000 = 0
T = 1414 lb
—————————————————————
Prob. 9.56
For the tie-back:
L = m 61.323 22
A = 0.7854(33)2 = 855 mm2
PV = 2 (122.6)/3.61
= 67.9 kN
MA : 67.9(3) = 58.9L
Max L = 3.46 m
—————————————————————
Prob. 9.57
103
9-8
Prob. 9.58
—————————————————————
Prob. 9.59
NOTES
104