F QFAB=0 F QFBA=0
A
6
=
B
A
l
B
i
A
B
=
M
= F
AB
i
M
= F
BA
i
F QFAB=0 F QFBA=0
编号
简图
=
1A
l
1
A
2
l
变形图
弯矩图(图中i 称为线 刚度，i=EI /l)
杆端弯矩 （以顺时针
转向为正）
B A = = A
B
B A
拐点
4i
B
A
拐点
6i/l
2i
M
= F
AB
4i
B
M
= F
BA
2i
6i/l
M
= F
AB
6i l
B
M
= F
BA
6i l
杆端剪力
F
= F
QAB
6i l
F
= F
QBA
6i l
表7-1 等截面杆件的固端弯矩和固端剪力（载常数）
编号
1A 4A 6A
简图 q l
FP
l q
l
变形图
弯矩图
BA
拐点
BA
拐点
BA
拐点
ql 2 BA
拐点
ql 2
F Pl
B8 A
拐点
FPl
8
ql 2 B
A
固端弯矩 （以顺时针
转向为正）
ql 2
M
= F
AB
B
ql 2 12
M
= F
BA
ql 2 12
固端剪力
F
= F
QAB
ql 2
F
= F
QBA
ql 2
FPl
8
M
= F
AB
FPl 8
B
M
= F
BA
FPl 8
F
= F
QAB
FP 2
F
= F
QBA
FP 2
B
M
= F
AB
ql 2 8
F
= F
QAB
5ql 8
F
= F
QBA
3ql 8
A
10 12 A
FP l /2 l /2
BA
拐点
q B
l
A
拐点
13 A
FP
B
l /2 l /2
FQFBA=0
B
FPl 8
M
= F
AB
M
= F
BA
3FPl 8
FPl 8
F
= F
QAB
F
P
FQFBA=0
B
M
= F
AB
FPl 2
FPl
M
= F
BA
2
FPl 2
F
= F
QAB
F
P
F
= F
QBA
F
P
FQRB=0
M B
M
= F
AB
M 2
M
= F
BA
M
F
= F
QAB
3M 2l
F
= F
QBA
3M 2l
表7-2 等截面杆件由杆端位移（或支座位移）引起的杆端弯矩和杆端剪力（形常数）
F
= F
QAB
12 i l2
F
= F
QBA
12 i l2
=
3A
l
= BA
=
BA 3i
B
M
= F
AB
3i
F
= F
QAB
3i l
F
= F
QBA
3i l
A
4
BA
1
= A
B
A
5
l
=
B
A
3i/l
B
A
B
B i
M
= F
AB
3i l
M
= F
AB
i
M
= F
BA
i
F
= F
QAB
3i l2
F
= F
QBA
3i l2
A
拐点
14 A 16 A
FP
A B
拐点
l
M
拐点
B
A
l
3FPl B 16
A 5FPl 32
ql 2
B
3
A
3FPl
B
8
A
FPl
B
2
A
BA
M 2
B
M
= F
AB
3FPl 16
F
= F
QAB
11F 16
P
F
= F
QBA5FP 16来自Bql 2 6
M
= F
AB
ql 2 3
M
= F
BA
ql 2 6
F
= F
QAB
ql