SKRIPTA RIJEÅ ENIH ZADATAKA IZ OTPORNOSTI MATERIJALA

39
Moment od sile FMi s obzirom na težište sustava
( ) ( ) ( )
kN
a
b
a
Q
a
a
b
a
Q
F
F
F
F
F
F
a
M
F
M
k
k
M
M
k
F
M
M
M
M
M
M
M
i
i
i
i
Mi
i
i
i
i
i
i
i
Mi
i
6
,
10
04
,
0
8
08
,
0
04
,
0
20
2
8
2
2
2
4
0
,
2
2
4
3
2
1
5
4
3
2
5
1
2
5
1
2
2
5
1
2
=
⋅
+
⋅
⋅
=
⋅
+
⋅
⋅
=
⋅
⋅
⋅
+
⋅
=
=
=
=
=
=
=
=
=
=
⋅
=
=
⇒
⋅
=
∑
=
⋅
=
⋅
=
∑
∑
∑
=
=
=
ρ
ρ
ρ
ρ
ρ
ρ
ρ
ρ
ρ
ρ
ρ
U srednjoj zakovici ne djeluje sila od momenta!
0
5 =
M
F
kN
F
F
R
kN
F
F
F
F
R
kN
F
F
F
F
R
kN
F
F
F
F
R
kN
F
F
F
F
R
kN
F
kN
F
Q
H
M
Q
M
H
M
Q
M
H
M
Q
M
H
M
Q
M
H
Q
H
66
,
4
49
,
10
2
2
2
2
17
,
6
2
2
2
2
57
,
12
2
2
2
2
15
,
15
2
2
2
2
4
5
20
4
,
2
5
12
2
2
5
2
2
4
2
2
3
2
2
2
2
2
1
=
+
=
=
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
−
+
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
+
=
=
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
−
+
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
−
=
=
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
+
+
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
−
=
=
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
+
+
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⋅
+
=
=
=
=
=
Najve�e optere�enje ima zakovica 1 : R1 = 15,15 kN
MPa
d
R
mA
F
s
20
,
49
4
014
,
0
2
15150
4
2
2
2
1
=
=
=
=
π
π
τ