Statics 2e 859
Problem 6.41
All members of the truss have the same length. Determine the force supported
by members BD,CD, and CE.
Problem 6.42
The structure shown below is supported by a pin at joint
A
and a horizontal link
at joint B. Determine the force supported by the members indicated below.
Members CE,DE, and DF .
Problem 6.43
The structure shown below is supported by a pin at joint
A
and a horizontal link
at joint B. Determine the force supported by the members indicated below.
Members EH ,FH , and F G.
Problem 6.44
The structure shown above is supported by a pin and roller on an inclined
surface that is parallel to the line connecting joints
A
and
G
. If
PD500 lb
,
determine the force supported by the members indicated below.
Members CD,CI , and IJ .
Problem 6.45
The structure shown above is supported by a pin and roller on an inclined
surface that is parallel to the line connecting joints
A
and
G
. If
PD500 lb
,
determine the force supported by the members indicated below.
Members DE,EI , and HI .
Problem 6.46
(a) By inspection, identify the zero-force members in the truss.
(b)
Of the zero-force members identified in Part (a), which could pos-
sibly be eliminated without reducing the strength of the truss? Ex-
plain.
(c) Find the force supported by member GH .
2.12 ft/Q.9ft/Q.6ft/Q.3ft/D0: (1)
)PyDQ: (2)
Using the cut shown above, the FBD shown at the right may be drawn.
Problem 6.47
(a) By inspection, identify the zero-force members in the truss.
(b)
Of the zero-force members identified in Part (a), which could possibly be
eliminated without reducing the strength of the truss? Explain.
(c) Find the force supported by member FH .
Problem 6.48
(a) By inspection, identify the zero-force members in the truss.
(b)
Of the zero-force members identified in Part (a), which could possibly be eliminated without reducing
the strength of the truss? Explain.
(c) Find the force supported by member F G.
XMFD0W 1kN .3m/C1kN .1m/FGH
2.1m/D0: (3)
)FGH D4
p2kN D 2:828 kN:(4)
Problem 6.49
The structure has a frictionless pulley at G.
(a) By inspection, identify the zero-force members in the truss.
(b)
Of the zero-force members identified in Part (a), which could
possibly be eliminated without reducing the strength of the truss?
Explain.
(c) Find the force supported by member GH .
(d) Find the force supported by member JK.
Problem 6.50
The electric power transmission tower supports two wires that apply
4kip
vertical forces, and the
8kip
horizontal force crudely models wind loading
during a storm.
(a) Determine if the truss is statically determinate or indeterminate.
(b)
Determine the force supported by the four members that emanate from
joint D.
Problem 6.51
(a) Determine if the truss is statically determinate or indeterminate.
(b) Determine the force supported by the five members that emanate from joint G.
Problem 6.52
A truss used for supporting signs over an expressway is shown. The truss is supported by a pin at joint A
and a horizontal link at joint B. Let WD500 lb.
Determine the force supported by the four members that emanate from joint E.
Problem 6.53
A truss used for supporting signs over an expressway is shown. The truss is supported by a pin at joint A
and a horizontal link at joint B. Let WD500 lb.
Determine the force supported by the four members that emanate from joint N.
Problem 6.54
A truss used for supporting signs over an expressway is shown. The truss is supported by a pin at joint A
and a horizontal link at joint B. Let WD500 lb.
Determine the force supported by the five members that emanate from joint I.
Problem 6.55
A truss used for supporting signs over an expressway is shown. The truss is supported by a pin at joint A
and a horizontal link at joint B. Let WD500 lb.
Without carrying out detailed calculations, answer the following questions.
(a)
The top chord of the truss has eight members (i.e., members
BD
,
DF
, …,
PR
). Are these members
in tension or compression? Which member of the top chord will have the absolute largest force?
Explain.
(b)
The bottom chord of the truss has eight members (i.e., members
AC
,
CE
, …,
OQ
). Are these
members in tension or compression? Which member of the bottom chord will have the absolute
largest force? Explain.
(c)
There are eight diagonal members of the truss (i.e., members
BC
,
DE
, …,
OR
). Which of these
members are in tension and which are in compression? Which diagonal member will have the
absolute largest force? Explain.
Problem 6.56
The boom of a tower crane is shown. The pulleys at A,B, and Qare frictionless, and WD10 kN.
(a) Determine the force supported by cable J T .
(b) Determine the force supported by the five members that emanate from joint J.
