Problems 753.ForceU 3 is maximum tensile, if distributed loadqis located within the portion
1.AC;2.KB;3.AB
4.If loadP is located at joint K then the force in members 5 and 6 are
1.D 5 >D 6 ;2.D 5 <D 6 ;3.D 5 DD 6.
(^1) h
3
(^256)
A B
EKC
a^4
d
Fig. P3.8
3.9.A single-span K-truss is shown in Fig.P3.9. Construct the influence lines for
the internal forces at the indicated members. Using the constructed influence lines,
calculate these forces if uniformly distributed loadqis distributed within the three
panels on the right and concentrated forcePis applied at the middle of the span.
a
d
D 1 D 2 a h
V
U
Fig. P3.9
Ans.UD
3
2
qd^2
h
CP
d
h
;VD
3
8
qd
P
4
;D 1 DD 2 D
3
8
qd
sin ̨
C
P
4 sin ̨
:
3.10 a,b.Two trusses with subdivided panels are presented in Fig.P3.10a, b. For
case (a) the diagonal members of the main truss are angled downward in the left
part of the truss and angled upward in the right part. In case (b) all the diagonal
members of the main truss are angled downward. Construct the influence lines for
the indicated members and compare the influence lines for the two cases. Using the
constructed influence lines, calculate these forces if loadPis placed at jointnand
uniformly distributed loadqis distributed within the panelA-n.
a
V
d n
A
b
V
A n
d
Fig. P3.10
Ans. (b)VD
qd
8
C
P
4
.