11,作各图所示梁的剪力图和弯矩图。
m
Q:
(kN)
60
20
210
8050
M:
(kNm)
YA=(10× 6× 6－ 20× 2)/6=53.33(kN)
YA
Q:
(kN)
30
23.33
6.67
20
M:
(kNm)
40
20
45
x
x=23.33× 3/30=2.33(m)
17.79
M:
(kNm)
5
10
45
1.67
18.33
30
0Q:
(kN)
YA=(－ 5+20× 3－ 10× 3× 1.5)/6=10/6(kN)
YA
1.2m
76
24
40
Q:
(kN)
130
M:
(kNm)
120
14.4
YA=(40× 8+10+20× 5× 2.5)/5=116 (kN)
YA
3.75
30
Q:
(kN)
5
M:
(kNm)
45
20
16.25
YA=(10× 3× 9.5+20× 4+5)/8=46.25 (kN)
YA
20
6
16
Q:
(kN)
12
M:
(kNm)
YB=(6× 8+6× 6× 3)/6=26kN
x=6× 16/36=8/3
64/3
YB
YA=(6× 6× 3－ 6× 2)/6=16 (kN)
YA