Timothy A. Philpot - Mechanics of materials _ an integrated learning system-John Wiley (2017)

pRoBLEmS
p17.30 Determine the horizontal displacement of joint B of
the two-bar assembly shown in Figure P17.30 if P = 80 kN. For
this structure, x 1 = 3.0 m, y 1 = 3.5 m, and x 2 = 2.0 m. Assume that
A 1 E 1 = 9.0 × 10 4 kN and A 2 E 2 = 38.0 × 10 4 kN.
A
L 1
(1)
B
a
B
P
C
Rigid bar
D
b
y 1
(1)
(2)
(2)
L 2
E
A
C
P
x 1 x 2
FIGURE p17.32
FIGURE p17.30
p17.31 Determine the vertical displacement of joint C of the
truss shown in Figure P17.31 if P = 215 kN. For this structure,
a = 3.5 m and b = 2.75 m. Assume that AE = 8.50 × 10 5 kN for all
members.
p17.33 Rigid bar ABC is supported by bronze rod (1) and
aluminum rod (2) as shown in Figure P17.33. A concentrated load
P = 90 kN is applied to the free end of aluminum rod (3). For this
structure, a = 800 mm and b = 500 mm. For bronze rod (1), L 1 = 1.8 m,
d 1 = 15 mm, and E 1 = 100 GPa. For aluminum rod (2), L 2 = 2.5 m,
d 2 = 25 mm, and E 2 = 70 GPa. For aluminum rod (3), L 3 = 1.0 m,
d 3 = 25 mm, and E 3 = 70 GPa. Determine the vertical displacement
of point D.
D
E
a
A
b
FIGURE p17.31
b
B
b
b
C
P
L 1
Bronze
(1)
a
Aluminum
(2)
b
L 2
p17.32 Rigid bar BCD in Figure P17.32 is supported by a pin at
C and by steel rod (1). A concentrated load P = 2.5 kips is applied
to the lower end of aluminum rod (2), which is attached to the rigid
bar at D. For this structure, a = 20 in. and b = 30 in. For steel rod (1),
L 1 = 50 in., A 1 = 0.4 in. 2 , and E 1 = 30,000 ksi. For aluminum rod (2),
L 2 = 100 in., A 2 = 0.2 in. 2 , and E 2 = 10,000 ksi. Determine the
vertical displacement of point E.
A
B
Aluminum
(3)
D
FIGURE p17.33
P
L 3
C
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