Information Technology Reference
In-Depth Information
beam of Fig. 5.5, we simply note that
w
=
0 and
θ
=
0 since the left end is fixed. The
a
a
conditions at the simply supported right end are
w
=
0 and M x = L
=
0. These are applied
x
=
L
to the first and fourth rows of (3). Equation (3), that is, z x = L
=
Uz a , can be written as
.
.
0
w =
0
U
U
w
w =
0
w
V
w
M
.
.
V
θ =
0
···
···
···
···
.
.
=
(4)
V
···
···
···
···
.
.
M 0
M
=
0
U MV
U MM
M
.
.
1
0
0
1
1
x
=
L
x
=
L
x
=
0
w
= θ
=
Cancel columns 1 and 2 because
0
0
0
θ
L and V x = L are unknown
where U kj and the loading vector components are the elements of U of (3). The equations
w
Ignore rows 2 and 3 because
x
=
0 are used to compute M a and V a , the remaining unknown initial
parameters. Thus from (4)
M
=
0 and M x = L
=
x
=
L
0
0
U w V
V a
M a
w
M 0
0
U w M
L =
=
+
(5)
U MV
U MM
x
=
x
=
L
x
=
L
or
0
L
0
=
V a U w V
+
M a U w M
+ w
(6)
M L
=
+
+
0
V a U MV
M a U MM
Equations (5) and (6) are solved for M a ,V a , giving
M 0 U w M
0 U MM
V a
= (
w
) |
/
x
=
L
(7)
0 U MV
M 0 U w V
M a
= (w
) |
/
x
=
L
where U ij and the loading components are the coefficients of the overall transfer matrix U
and
∇= (
U
w
V U MM
U
w
M U MV
) |
(8)
x
=
L
For the beam of Fig. 5.5, (3) gives
.
3
EI
2
p 0
4
EI
4
3
2
8
15
1
2
EI
.
3
2
2
EI
2
EI
p 0
01
EI
0 .
00
1
p 0
U
=
(9)
.
2
4 p 0
00 2
1
3
.
···
···
···
···
···
0 .
00
0
1
4
EI
2
8
15
p 0
and M L = 4 p 0
L
Introduce the boundary conditions to (9) or use (7) with
w
=
to
3
find the initial parameters V a and M a . Thus,
V a
M a
3
EI
2
4
4
3
2
8
15
p 0
EI
EI
=
(10)
2
4 p 0
2
1
3
Search WWH ::




Custom Search