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8/6/2019 06 Matrix Beam
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1
! Development: The Slope-Deflection
Equations
! Stiffness Matrix
! General Procedures
! Internal Hinges
! Temperature Effects
! Force & Displacement Transformation! Skew Roller Support
BEAM ANALYSIS USING THE STIFFNESS
METHOD
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2
Slope Deflection Equations
settlement = j
Pi j kw
Cj
Mij Mjiw
P
j
i
i j
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3
Degrees of Freedom
L
A B
M
1 DOF:
P
A
B
C 2 DOF: ,
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4
L
A B
1
Stiffness Definition
kBAkAA
L
EIkAA
4=
LEIkBA 2=
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5
L
A B1
kBBkAB
L
EIkBB
4=
LEIkAB 2=
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6
Fixed-End Forces
Fixed-End Forces: Loads
P
L/2 L/2
L
w
L
8
PL
8
PL
2
P
2
P
12
2wL
12
2wL
2
wL
2
wL
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7
General Case
settlement = j
Pi j kw
Cj
Mij Mjiw
P
j
i
i j
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8
wP
settlement = j
(MFij) (MFji)
(MFij)Load (MFji)Load
+
Mij Mji
i
j
+
i jwP
MijMji
settlement = jj
i
=+ ji L
EI
L
EI
24
jiL
EI
L
EI
42
+=
,)()()2
()4
( LoadijF
ijF
jiij MML
EI
L
EIM +++= Loadji
Fji
F
jiji MML
EI
L
EIM )()()
4()
2( +++=
L
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9
Mji Mjk
Pi j kwCj
Mji Mjk
Cj
j
Equilibrium Equations
0:0 =+=+ jjkjij CMMM
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10
+
1
1
i jMij Mji
i
j
L
EIkii
4=
L
EIkji
2=
L
EIkij
2=
L
EIkjj
4=
i
j
Stiffness Coefficients
L
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11
[ ]
=
jjji
ijii
kk
kkk
Stiffness Matrix
)()2
()4
( ijF
jiij ML
EI
L
EIM ++=
)()4
()2
( jiF
jiji M
L
EI
L
EIM ++=
+
=
F
ji
F
ij
j
iI
ji
ij
M
M
LEILEI
LEILEI
M
M
)/4()/2(
)/2()/4(
Matrix Formulation
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12
[D] = [K]-1([Q] - [FEM])
Displacement
matrix
Stiffness matrix
Force matrixw
P(MFij)Load (MFji)Load
+
+
i jwP
MijMji
j
i
j
Mij Mji
i
j
(MFij) (MFji)
Fixed-end moment
matrix
][]][[][ FEMKM +=
]][[])[]([ KFEMM =
][][][][1 FEMMK =
L
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L
Real beam
Conjugate beam
Stiffness Coefficients Derivation
MjMi
L/3
i
MM ji +
I
Mj
I
Mi
I
LMj
2
I
LMi
2
)1(2
0)3
2)(
2()
3)(
2(:0'
=
=+=+
ji
jii
MM
L
EI
LML
EI
LMM
)2(0)2
()2
(:0 =+=+ILM
ILMF jiiy
ij
ii
EI
M
L
EIM
andFrom
)
2
(
)4
(
);2()1(
=
=
MM ji +
i j
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Derivation of Fixed-End Moment
Real beam
8,0
162
22:0
2
PLMI
PLI
MLI
MLFy ==+=+
P
M
MI
M
Conjugate beam
A
I
M
B
L
P
A B
I
M
I
ML
2
I
M
I
ML
2
IPL16
2
IPL4 I
PL16
2
Point load
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15
L
P
841616
PLPLPLPL
=+
+
8
PL
8
PL
2
P
2
PP/2
P/2
-PL/8 -PL/8
PL/8
-PL/16-PL/8
-
PL/4
+
-PL/16-PL/8
-
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16
Uniform load
L
w
A B
w
M
M
Real beam Conjugate beam
A
I
M
I
M
B
12,0
242
22:0
23
wLMI
wLI
MLI
MLFy ==+=+
IwL8
2
I
wL
24
3
I
wL
24
3
I
M
I
ML
2
I
M
I
ML
2
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17
Settlements
M
M
L
MjMi = Mj
L
MM ji +MM ji +
Real beam
26LEIM =
Conjugate beam
I
M
A B
I
M
,0)3
2)(
2()
3)(
2(:0 =+=+
L
I
MLL
I
MLMB
I
M
I
ML
2
I
M
I
ML
2
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Typical Problem
0
0
0
0
A C
B
P1P2
L1 L2
wCB
80
24 11
11
LP
L
EI
L
EIM BAAB +++=
8
042 11
11
LP
L
EI
L
EIM BABA ++=
1280
242
222
22
wLLP
L
EI
L
EIM CBBC ++++=
1280
422
222
22
wLLP
L
EI
L
EI
M CBCB
+++=
P
8
PL
8
PL
L
w12
2wL
12
2wL
L
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MBA MBC
A C
B
P1P2
L1 L2
wCB
B
CB
80
42 11
11
LP
L
EI
L
EIM BABA ++=
128
024
2
222
22
wLLP
L
EI
L
EIM CBBC ++++=
BBCBABB forSolveMMCM ==+ 0:0
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A C
B
P1P2
L1 L2
wCB
Substitute B
in MAB
, MBA
, MBC
, MCB
MABMBA
MBCMCB
0
0
0
0
80
24 11
11
LP
L
EI
L
EIM BAAB +++=
80
42 11
11
LP
L
EI
L
EIM BABA ++=
1280
242
222
22
wLLP
L
EI
L
EIM CBBC ++++=
1280
422
222
22
wLLP
L
EI
L
EIM CBCB
+++=
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A B
P1
MAB
MBA
L1
A CB
P1P2
L1 L2
wCB
ByR CyAy ByL
Ay Cy
MABMBA
MBCMCB
By = ByL +ByR
B CP2
MBC
MCB
L2
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2EI EI
Stiffness Matrix
Node and Member Identification
Global and Member Coordinates
Degrees of Freedom
Known degrees of freedomD4,D5, D6, D7, D8 andD9 Unknown degrees of freedomD1, D2 andD3
1 21 2 31
2 3
7
8
9
4
5
6
1
2 3
7
8
9
4
5
6
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i j
E, I, A, L
Beam-Member Stiffness Matrix
d4 = 1
AE/LAE/L AE/L AE/L
6
4
5
1
2
3
[k] =
1 2 3 4 5 6
3
2
1
4
6
5
d1 = 1
k11= = k44
0
0
0
0
0
0
0
0
-AE/LAE/L
-AE/L AE/L
k41 k14
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d2 = 1
[k] =
1 2 3 4 5 6
3
2
1
4
6
5
0
0
0
0
0
0
0
0
-AE/LAE/L
-AE/L AE/L
6EI/L2
6EI/L2
d5
= 1
6EI/L2
6EI/L2
12EI/L312EI/L3 12EI/L3
12EI/L3
6EI/L2
12EI/L3
- 6EI/L2
- 12EI/L3
0
0
6EI/L2
-12EI/L3
0
0
- 6EI/L2
12EI/L3
k22= = k55
= k52
k62 =
= k32= k65
= k25
= k35
i j
E, I, A, L6
4
5
1
2
3
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[k] =
1 2 3 4 5 6
3
2
1
4
6
5
0
0
0
0
0
0
0
0
-AE/LAE/L
-AE/L AE/L
6EI/L2
12EI/L3
- 6EI/L2
- 12EI/L3
0
0
6EI/L2
-12EI/L3
0
0
- 6EI/L2
12EI/L3
4EI/L
6EI/L2 6EI/L2
2EI/L
0
0
2EI/L
-6EI/L2
0
0
-6EI/L2
4EI/L
d6 = 1
d3 = 1 2EI/L4EI/L
6EI/L26EI/L26EI/L2
4EI/L 2EI/L
6EI/L2
k33=
k23= = k53
= k63 = k36
= k56k26=
= k66
i j
E, I, A, L6
4
5
1
2
3
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27
+
=
F
j
F
yi
F
xj
F
i
F
yi
F
xi
j
j
j
i
i
i
j
yj
xj
i
yj
xi
M
FF
M
F
F
LEILEILEILEI
LEILEILEILEILAELAE
LEILEILEILEI
LEILEILEILEI
LAELAE
M
FF
M
F
F
/4/60/2/60
/6/120/6/12000/00/
/2/60/4/60
/6/120/6/120
00/00/
22
2323
22
2323
F
jjjjiiij
F
yjjjjiiiyj
F
xijjjiiixj
F
ijjjiiixi
F
yijjjiiiyi
F
xijjjiiixi
MLEILEILEILEIM
FLEILEILEIF
FLAELAEFMLEILEILEILEIM
FLEILEILEILEIF
FLAELAEF
)/4()/6()0()/2()/6()0(
)/6()0()0()/6()/12()0(
)0()0()/()0()0()/()/2()/6()0()/4()/6()0(
)/6()/12()0()/6()/12()0(
)0()0()/()0()0()/(
22
223
22
2323
=
=
==
+=
+++++=
[q] = [k][d] + [qF]
Fixed-end force matrix
End-force matrix
Stiffness matrix
Displacement matrix
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6x6 Stiffness Matrix
[ ]
=
LEILEILEILEI
LEILEILEILEI
LAELAE
LEILEILEILEI
LEILEILEILEI
LAELAE
k
/4/60/2/60
/6/120/6/120
00/00/
/2/60/4/60
/6/120/6/120
00/00/
22
2323
22
2323
66
i j ji ji
Mi
Vj
Mj
Vi
Nj
Ni
4x4 Stiffness Matrix
[ ]
=
LEILEILEILEI
LEILEILEILEI
LEILEILEILEILEILEILEILEI
k
/4/6/2/6
/6/12/6/12
/2/6/4/6/6/12/6/12
22
2323
22
2323
44
i j ji
Mi
Vj
Mj
Vi
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Comment:- When use 4x4 stiffness matrix, specify settlement.
- When use 2x2 stiffness matrix, fixed-end forces must be included.
2x2 Stiffness Matrix
i jMiMj
[ ]
=
LEILEI
LEILEIk
/4/2
/2/422
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30
2131
2
1
2
3
4
5
6
General Procedures: Application of the Stiffness Method for Beam Analysis
wP P2y
M2M1
Local
1
2
3
4
1
1
2
3
4
2
Global
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31
Member
1
2
3
4
1
3
4
5
6
2
1
2
3
4
5
6
312
1 2Global
wP P2y
M2M1
Local
1
2
3
4
1
1
2
3
4
2
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32
(q F4 )2
(qF
3 )2
(q F1)2
(qF
2)2
w
2
P
(q F4)1
(qF
3)1
(q F2)1
(q F1 )1
1[FEF]
1
2
3
4
5
6
312
1 2Global
Local
1
2
3
4
1
1
2
3
4
2
wP P2y
M2M1
2 4 6
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33
[q] = [T]T[q]
1
2
3
4
5
6
31
21 2Global
Local
1
2
3
4
1
[k] = [T]T[q] [T]
=
'4
'3
'2
'1
4
3
2
1
10000100
0010
0001
q
q
q
q
1 42 3
1
2
34
1
2 4 6
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[q] = [T]T[q]
1
2
3
4
5
6
31
21 2
Global
Local
1
2
3
4
2
[k] = [T]T[q] [T]
=
'4
'3
'2
'1
6
5
4
3
10000100
0010
0001
q
q
q
q
1 42 3
3
4
56
2
2 4 6
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35
Stiffness Matrix:
21
31
2
1
2
3
4
5
6
[k]1 =
1
2
3
4
1 2 3 4
[k]2 =
3
4
5
6
3 4 5 6
Member 1
[K] =
1
23
4
5
6
1 2 3 4 5 6
Member 2
Node 2
1 2
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36
+
=
F
F
F
F
F
F
Q
Q
Q
Q
D
D
D
D
D
D
Q
Q
Q
Q
Q
Q
6
5
1
4
3
2
6
5
1
4
3
2
6
5
1
4
3
2 2
3
4
15
6
5 612 3 4
0
0
0
M1z
-P2y
M3z
KBA
KAB
KBB
KAA
2131
2
1
2
3
4
5
6
Reaction
Qu
Joint Load
Qk
Du=Dunknown
Dk= D
known
QFB
QFA
[ ] [ ][ ] FAuAAk QDKQ +=
[ ] [ ] [ ] [ ])(1 FAkAAu QQKD +=
[ ] [ ][ ]F
qdkqForceMember +=:
Global: 2 4 62 4 6
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37
+
6
5
4
3
2
1
D
D
D
DD
D
Global:
21 3
1
2
1
2
3
4
5
6
12
2
3
4
51
6
(q F6 )2
(q F5 )2
(qF4)2
(qF3)2
w
2
P
(qF4)1
(qF3)1
(qF2)1
(qF1 )1
1[FEF]
=
=
=
24
23
12
MQ
PQ
MQ
y
4
3
2
D
D
D
+F
F
F
Q
Q
Q
4
3
2
2 3 4
Node 2
=
2
3
4
Member 1
1
23
4
5
6
1 2 3 4 5 6
Member 2
Node 2=
6
5
4
3
2
1
Q
Q
Q
Q
+=
+=
F
F
F
4
F
4
F
F
3
F
3
F
F
F
Q
Q
qqQ
qqQQ
Q
6
5
214
213
2
1
)()(
)()(M1-P2y
M2
0
0
0
2 4 6
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38
12
31
21
2
3
4
5
6
4
3
2
D
D
D
2 3 4
Node 2
=
2
3
4
=
=
=
F
F
F
Q
Q
Q
MQ
PQ
MQ
4
3
2
24
2y3
12
2 4 6
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39
Member 1:
21 3
1
21 3 5
P
qF4
qF3
qF2
qF1
1
[FEF]
4
3
2
1
q
q
=
==
=
44
33
22
1 0
Dd
DdDd
d
+
F
F
F
F
q
q
4
3
2
11
23
4
1 2 3 4
= 1k
2 4 6
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21 3
1
21 3 5
Member 2:
qF6
qF5
qF4qF3
w
2
[FEM]
6
5
4
3
q
q
=
==
=
0
0
6
5
44
33
d
dDd
Dd
+
F
F
F
F
q
q
6
5
4
31
2
3
4
1 2 3 4
= 1k
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A
CB
9 m 3 m
10 kN
1 kN/m
1.5 m
Example 1
For the beam shown, use the stiffness method to:
(a) Determine the deflection and rotation atB.
(b) Determine all the reactions at supports.
(c) Draw the quantitative shear and bending moment diagrams.
10 kN
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42
21Global
123
1Members
23
2
12
A
CB
9 m 3 m
10 kN
1 kN/m
1.5 m
wL2/12 = 6.75wL2/12 = 6.75 PL/8 = 3.75PL/8 = 3.75
10 kN
1.5 m1.5 m
2
1 kN/m
9 m 1[FEF]
123 123
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4/3
2/3
2/3
21
9 m 3 m
[k]1= EI4/9
2/9
3
4/9
2/92
3
2[k]2 = EI
4/3
4/3
2/3
2/3
2 12
1
[K] = EI
2 1
2
1
(4/9)+(4/3)
21
Stiffness Matrix:i j
MiMj
[ ]
=
LEILEI
LEILEIk
/4/2
/2/422
10 kN 123
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44
A C
B
1 kN/m
Equilibriumequations: MCB = 0
MBA + MBC= 0
Global Equilibrium: [Q] = [K][D] + [QF]
=2.423/EI
0.779/EI
C
B
9 m 1.5 m1.5 m
6.756.75
+-3.75
-6.75 + 3.75 = -3MBA+ MBC= 0
MCB= 01
2
C
B
4/3
2/3
2/3= EI
2 1
2
1
(4/9)+(4/3)
3.753.756.75
23
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45
=-6.40
6.92
Member 1 : [q]1 = [k]1[d]1 + [qF]1
MBA
MAB
2
3
= 0.779/EIB
A0
+-6.75
6.75
Substitute B and Cin the member matrix,
1
2
wL2/12 = 6.75wL2/12 = 6.75
1 kN/m
9 m 1[FEF]
4.56 kN 4.44 kN
6.92 kNm 6.40 kNm
wL2/12 = 6.75wL2/12 = 6.75
= EI4/9
2/9
3
4/9
2/9
2
1 kN/m
19 m
10 kN
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Member 2 : [q]2 = [k]2[d]2 + [qF]2
Substitute B and Cin the member matrix,
MCB
MBC
1
2
= EI4/3
4/3
2/3
2/3
2 1
=0
6.40
C
B
= 2.423/EI
= 0.779/EI
2
12
[FEF]
PL/8 = 3.75PL/8 = 3.75
1.5 m1.5 m
2
7.13 kN 2.87 kN
6.40 kNm
10 kN
2
PL/8 = 3.75PL/8 = 3.75
+-3.75
3.75
1 kN/m
10 kN
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A C
B
10 kN1 kN/m
9 m 1.5 m1.5 m
6.92 kNm
11.57 kN 2.87 kN4.56 kN
4.56 kN 4.44 kN 7.13 kN 2.87 kN
1 kN/m
6.92 6.406.40
M
(kNm) x (m)
-6.92 -6.40
3.48 4.32
V(kN)x (m)
4.56
-4.44-2.87
4.56 m
7.13
B = +0.779/EIC= +2.423/EI
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20 kN
A CBEI2EI
4 m 4 m
9kN/m 40 kNm
Example 2
For the beam shown, use the stiffness method to:
(a) Determine the deflection and rotation atB.
(b) Determine all the reactions at supports.
2 4 62 6
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1 2 3
0.5625
3
-0.375
-0.375
1 3 5
[K] =EI
3 4
3
4
Use 4x4 stiffness matrix,
[k]1
0.375EI
-0.75EI2EI
0.75EI - 0.375EI
0.375EI
0.75EI
EI
-0.75EI
2EI
0.75EI
0.75EI
-0.375EI
EI
-0.75EI
-0.75EI
1 2 3 4
1
2
3
4
[k]2
0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
0.1875EI
-0.375EIEI
0.375EI- 0.1875EI
0.1875EI
0.375EI
0.5EI
-0.375EI
EI
3 4 5 6
3
4
5
6
2 EI EI
1 2
1 5
i j j
Mi
i
Vj
Mj
Vi
[ ]
=
LEILEILEILEI
LEILEILEILEI
LEILEILEILEI
LEILEILEILEI
k
/4/6/2/6
/6/12/6/12
/2/6/4/6
/6/12/6/12
22
2323
22
2323
20 kN20 kN
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9kN/m 40 kNm
4 m 4 m
12 kNm
18 kN
12 kNm
18 kN 18 kN
D4
D3
Global:
D4
D3=
9.697/EI
-61.09/EI
Q4 = 40
Q3 = -203
4+
-12
18 3
4
40 kNm
12 kNm
1 2
1
2
3
4
5
6
1 2 3
2EI EI
[Q] = [K][D] + [QF]
0.5625
3
-0.375
-0.375
=EI
3 4
3
4
9 kN/m
2 4
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Member 1:
1
9 kN/m
A B
12 kNm
[qF]1
12 kNm
18 kN 18 kN
1
9 kN/m
A B
[q]1
53.21 kNm
48.18 kN
67.51 kNm12.18 kN
1
1 3
1 2
2EI 12 kNm 12 kNm
18 kN 18 kN
q2
q1
q4L
q3L
67.51
48.18
53.21
-12.18
12
18
-12
18
12(2EI)/43
-0.75EI2EI
0.75EI - 0.375EI
0.375EI
0.75EI
EI-0.75EI
2EI
0.75EI
0.75EI
-0.375EI
EI
-0.75EI
-0.75EI
1 2 3 4
1
2
3
4
[q]1 = [k]1[d]1 + [q
F
]1
d3 = -61.09/EI
d4 = 9.697/EI
d2 = 0
d1 = 0
4 6
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2B C
[q]2
Member 2:
[q]2 = [k]2[d]2 + [qF]2
2
3 5
2 3
EI
q4R
q3R
q6
q5
0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
0.1875EI
-0.375EIEI
0.375EI- 0.1875EI
0.1875EI
0.375EI
0.5EI
-0.375EI
EI
3 4 5 6
3
4
5
6
0
0
0
0
d3 =-61.09/EI
d4 = 9.697/EI
d6 = 0
d5 = 0
18.06 kNm
7.82 kN
13.21 kNm
7.82 kN
-13.21
-7.818
-18.06
7.818
9 kN/m 53.21 kNm
18.06 kNm13.21 kNm
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V(kN)x (m)
-7.818
48.18
-7.818-
M
(kNm)x (m)
13.21
-18.08-
-67.51
-
1A B
[q]148.18 kN67.51 kNm
12.18 kN
2B C
[q]27.82 kN7.82 kN
12.18+
53.21
+
20 kN
4 m 4 m
9kN/m 40 kNm
7.818 kN
18.06 kNm67.51 kNm
48.18 kN
D3=
B= -61.09/EI
D4 = B = +9.697/EI
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9kN/m
10 kN
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Global1 2
1
2
3
4
5
6
1 2 3
A CB EI2EI
9kN/m 40 kNm
4 m 2 m 2 m
10 kN
5 kNm
5 kN
5 kNm
5 kN
2
12 kNm
18 kN
12 kNm
18 kN
9 kN/m
1[FEF]
i j j
Mi
i
Vj
Mj
Vi
[ ]
=
LEILEILEILEI
LEILEILEILEI
LEILEILEILEI
LEILEILEILEI
k
/4/6/2/6
/6/12/6/12
/2/6/4/6
/6/12/6/12
22
2323
22
2323
44
2 4 62
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1 2
1 3 5
1 2 3
4 m 2 m 2 m
1 5
1 2
0.375
0.5
0.375 0.5 1
[K] = EI
3 4 6
3
4
6
0.5625
3
-0.375
-0.375
12(2EI)/43
[k]1 =-0.75EI2EI
0.75EI - 0.375EI
0.375EI
0.75EI
EI
-0.75EI
2EI/L
0.75EI
0.75EI
-0.375EI
EI
-0.75EI
-0.75EI
1 2 3 41
2
3
4
[k]2 =0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
0.1875EI
-0.375EIEI0.375EI - 0.1875EI
0.1875EI
0.375EI0.5EI
-0.375EI
EI
3 4 5 6
3
4
5
6
20 kN
9kN/m 40 kN
10 kN20 kN
40 kN
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MBA+MBC= 40
VBL+VBR = -20
MCB = 0B
B
C-12 + 5 = -7-5
B
B
C
= -7.667/EI-116.593/EI
52.556/EI
Global: [Q] = [K][D] + [QF]
= EI
0.5625
3
-0.375
-0.375
0.375
0.50.375 0.5 1
3 4 6
3
46
A CB
9kN/m 40 kNm
21
1
2
3
4
5
6
1 2 310 kN5 kNm
5 kN
5 kNm
5 kN
2
12 kNm
18 kN
12 kNm
18 kN
9 kN/m
1[FEF]
40 kNm
5 kNm5 kNm
5 kN
12 kNm
18 kN
+18 + 5 = 23
1
2
3
4
12 kNm9 kN/m
12 kNm
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0.375EI
=
-0.75EI2EI
0.75EI - 0.375EI
0.375EI
0.75EI
EI
-0.75EI
2EI/L
0.75EI
0.75EI
-0.375EI
EI
-0.75EI
-0.75EI
1 2 3 4
1
2
3
4
=
91.78
55.97
60.11
-19.97
91.78 kNm
55.97 kN
Member 1: [q]1 = [k]1[d]1 + [qF]1
MAB
VA
MBA
VBL +
12
18
-12
18=-116.593/EI
=-7.667/EI
0
0
B
B
1
1 3
1 2
12 kNm
18 kN
12 kNm
18 kN1
[FEF]
19.97 kN
60.11 kNm4 m
9kN/m
1
12 kNm
18 kN
12 kNm
18 kN18 kN
10 kN5 kNm
k
64
5 kNmk
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VC
MBC
VBR
MCB
+
5
5
5
-5
=
-20.11
-0.0278
0
10.03
=52.556/EI
=-116.593/EI
=-7.667/EIB
B
C
0
5 kN m
5 kN
5 kNm
5 kN
2
[FEM]
10.03 kN
2 m
10 kN
2 m
2
=
0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
0.1875EI
-0.375EIEI
0.375EI - 0.1875EI
0.1875EI
0.375EI
0.5EI
-0.375EI
EI
3 4 5 6
3
4
5
6
0.0278 kN
20.11 kNm
Member 2: [q]1 = [k]1[d]1 + [qF]1
223
535 kN m
5 kN
5 kNm
5 kN
91.78 kNm9kN/m 20.11 kNm
2 m
10 kN
2 m91.78 kNm20.11 kNm
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20 kN
4 m 2 m
9kN/m 40 kNm
10 kN
2 m
10.03 kN
91.78 kNm
55.97 kN
V(kN)x (m)
55.97
-0.0278
19.97
+
-10.03 -10.03
-
55.97 kN 19.97 kN60.11 kNm4 m
1
10.03 kN0.0278 kN
2
60.11 kNm
M
(kNm) x (m)
-91.78
-
+20.11
60.11
B = -7.667/EI
C= 52.556/EI
B = -116.593/EI
Example 4
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61
40 kN
8 m 4 m 4 m
2EI EI
6 kN/m
AB
C
B = -10 mm
p
For the beam shown:(a) Use the stiffness method to determine all the reactions at supports.
(b) Draw the quantitative free-body diagram of member.
(c) Draw the quantitative shear diagram, bending moment diagram
and qualitative deflected shape.
TakeI= 200(106) mm4 andE= 200 GPa and supportB settlement 10 mm.
1 2 3
2 EI EI
1
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[k]1 =4
8
8
4
1 2
1
2
EI8
1 2
2 EI EI
2
42
2 3
2
3
[K] = EI812
2
4
4
2
2 3
2
3
[k]2 =EI8
Use 2x2 stiffness matrix:
i jMiMj[ ]
= LEILEI
LEILEI
k /4/2
/2/422
40 kN6 kN/m
B C
1 2 3
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75 kNm
6(2EI)/L2 = 75 kNm
10 mm
137.5 kNm
6(EI)/L2
= 37.5 kNm
10 mm
2
[FEM]
6(EI)/L2
= 37.5 kNm
D2
D3
=
-61.27/EI rad
185.64/EI rad
2EI EIA B = -10 mm 1 2
[FEM]load
32 kNmwL2/12 = 32 kNm
6 kN/m
1 40 kNmPL/8 = 40 kNm2
40 kN
8 m 4 m 4 m
32 kNm 40 kNmPL/8 = 40 kNm
75 kNm37.5 kNm
+
-32 + 40 + 75 -37.5 = 45.5Q2= 0
Q3 = 0 -40 - 37.5 = -77.5
D2
D3
2
42
2 3
2
3
12
8
EI
=
Global: [Q] = [K][D] + [QF]
[FEM]load
6 kN/m2
2EI
1
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6(2EI)/L2 = 75 kNm
32 kNmwL2/12 = 32 kNm1
75 kNm
6(2EI)/L2 = 75 kNm10 mm
1[FEM]
6 kN/m
18 m
1
q1
q2
d1 = 0
d2 = -61.27/EI=
76.37 kNm
-18.27 kNm
Member 1: [q]1 = [k]1[d]1 + [qF]1
32 kNmwL2/12 = 32 kNm
75 kNm
+32 + 75 = 107
-32 + 75 = 43
31.26 kN
76.37 kNm
16.74 kN
18.27 kNm
4
8
8
4
1 2
1
28
EI=
2 3 40 kN
[FEM]
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Member 2: [q]2 = [k]2[d]2 + [qF]2
2 40 kNmPL/8 = 40 kNm 2
37.5 kNm
6(EI)D/L2 = 37.5 kNm
10 mm
2
[FEM]load
[FEM]
40 kNm
37.5 kNm
6(EI)D/L2 = 37.5 kNm
PL/8 = 40 kNm
=18.27 kNm
0 kNm
q2
q3
+40 - 37.5 = 2.5
-40 - 37.5 = -77.5
d2 = -61.27/EI
d3 = 185.64/EI
17.72 kN
18.27 kNm
22.28 kN
40 kN
2
2
4
4
2
2 3
2
38
EI=
2 EI EI
264
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Alternate method: Use 4x4 stiffness matrix
1 253
1
8
EI= 1.5
1.5
-0.375
12(2)/82
4
-1.5
8
1.5
-1.5
-1.5
-0.375
0.375
1.5
4
-1.5
8
1 2 3 4
1
2
3
4
[k]1
8
EI=
0.75
0.75
-0.1875
12/82
2
-0.75
4
0.75
-0.75
-0.75
-0.1875
0.1875
0.75
2
-0.75
4
3 4 5 6
3
4
5
6
[k]2
2
-0.75
-0.1875
-0.75
0.1875
-0.75
0.75
2
-0.75
4
-0.1875
0.75
1.5 4
1.5
4
0.375
-0.3751.5
1.5
8-1.5
-0.375
-1.5
0
0
0
0
0
0
0
0
-0.75
12
0.5625
-0.758
EI=[K]
1
23
4
5
6
1 4 5 62 3
40 kN6 kN/m
B C
264
2
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Global: [Q] = [K][D] + [QF]
8 m 4 m 4 m
2EI EIA B = -10 mm 12
531
40 kN40 kNm
20 kN
40 kNm
20 kN
232 kNm
24 kN
32 kNm
24 kN
6 kN/m
1[FEF]
531
D4
D6 =
-61.27/EI= -1.532x10-3 rad
185.64/EI= 4.641x10-3 rad
+(200x200/8)(-0.75)(-0.01) = 37.5
(200x200/8)(0.75)(-0.01) = -37.5
D4
D6
Q4= 0
Q6= 0
2
4
12
2+
8
-40
4 6
4
68
EI=
-0.75
-0.75 D5 = -0.01)8
200200(
+ 4
6
5
D4
D6
Q4= 0
Q6= 0
2
4
12
2
4 64
68
EI= +
8
-40
24
32 kNm6 kN/m
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+
32
24
-32
24
q1
q2
q4
q3
1.5
1.5
-0.375
12(2)/82
4
-1.5
8
1.5
-1.5
-1.5
-0.375
0.375
1.5
4
-1.5
8
1 2 3 4
1
2
34
=(200x200)
8
q1
q2
q4
q3=
76.37 kNm
31.26 kN
-18.27 kNm
16.74 kN
Member 1: [q]1 = [k]1[d]1 + [qF]1
13
1 B = -10 mm32 kNm
24 kN
32 kN m
24 kN
1[FEF]load
d2 = 0
d1 = 0
d4 = -1.532x10-3
d3 = -0.01
6 kN/m
18 m
31.26 kN
76.37 kNm
16.74 kN
18.27 kNm
6440 kN
40 kNm40 kNm
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Member 2:
+40
20
-40
20
q3
q4
q6
q5
d4 = -1.532x10-3
d3 = -0.01
d6 = 4.641x10-3
d5
= 0
0.75
0.75
-0.1875
12/82
2
-0.75
4
0.75
-0.75
-0.75
-0.1875
0.1875
0.75
2
-0.75
4
3 4 5 63
4
5
6
=(200x200)
8
q3
q4
q6
q5=
18.27 kNm22.28 kN
0 kNm
17.72 kN
17.72 kN
18.27 kNm
22.28 kN
40 kN
2
2
53
-10 mm = B
20 kN20 kN
2
[FEF]
40 kN6 kN/m
B C76.37 kNm
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8 m 4 m 4 m
2EI EIA B = -10 mm31.26 kN 16.74 + 22.28 kN 17.72 kN
V(kN)x (m)
+ +--
31.26
-16.74
22.28
-17.725.21 m
M
(kNm) x (m)
-76.37
5.06
-18.27
70.85
+
--
D6 = C= 4.641x10-3 rad
d4 = B = -1.532x10-3
rad
Deflected
Curve
B = -10 mm
Example 5
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71
For the beam shown:(a) Use the stiffness method to determine all the reactions at supports.
(b) Draw the quantitative free-body diagram of member.
(c) Draw the quantitative shear diagram, bending moment diagram
and qualitative deflected shape.
TakeI= 200(106) mm4 andE= 200 GPa and support Csettlement 10 mm.
4 kN
8 m 4 m 4 m
2EI EI
0.6 kN/m
AB C
C= -10 mm
20 kNm
2 EI EI
264
2
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72
12
-10 mm53
15
1
Q3
Q6
Q4
0.75 2
0.75
2
4
1.5
1.5
-0.375
12(2)/82
4
-1.5
8
1.5
-1.5
-1.5
-0.375
0.375
1.5
4
-1.5
8
1 2 3 4
1
2
3
4
[k]1
8
EI=
8
EI=
0.75
0.75
-0.1875
12/82
2
-0.75
4
0.75
-0.75
-0.75
-0.1875
0.1875
0.75
2
-0.75
4
3 4 5 6
3
4
5
6
[k]2
D3
D6
D4
-0.1875
-0.75
-0.75 D5 = -0.01
Global: [Q] = [K][D] + [QF]
Member stiffness matrix [k]4x4
0.5625
-0.75
-0.75
12
3
4
6
3 4 6
8
EI= )
8
200200(
+
3
4
6
5
QF3
QF6
QF4+
4 kN0.6 kN/m
A
BC
20 kNm2 EI EI
1 2
642
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4 kN4 kNm
2 kN
4 kNm
2 kN
23.2 kNm
2.4 kN
3.2 kNm
2.4 kN
0.6 kN/m
1[FEF]
8 m 4 m 4 m2EI
EIA10 mm
1 2
3 51
3
4
6
0.5625
0.75
-0.75
-0.75
12
2
0.75
2
3 4 6
48
EI=
D3
D6
D4 +
9.375
37.5
37.5
2.4+2 = 4.4
-4.0
-3.2+4 = 0.8+
D3
D6
D4
-377.30/EI= -9.433x10-3 m
+74.50/EI= +1.863x10-3 rad
-61.53/EI= -1.538x10-3 rad=
Global: [Q] = [K][D] + [QF]
Q3 = 0
Q6 = 20
Q4 = 0
24
3 2 kNm3.2 kNm
0.6 kN/m
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+3.2
2.4
-3.2
2.4
q1
q2
q4
q3
q1
q2
q4
q3=
43.19 kNm
8.55 kN
6.03 kNm
-3.75 kN
Member 1: [q]1 = [k]1[d]1 + [qF]1
d2 = 0
d1 = 0
d4 = -1.538x10-3
d3 = -9.433x10-3
0.6 kN/m
18 m
8.55 kN
43.19 kNm
3.75 kN
6.03 kNm
13
1
3.2 kNm
2.4 kN2.4 kN
1[FEF]load 8 m
1.5
1.5
-0.375
12(2)/82
4
-1.5
8
1.5
-1.5
-1.5
-0.375
0.375
1.5
4
-1.5
8
1 2 3 4
1
2
3
48
200200=
644 kN
4 kNm4 kNm
[FEF]
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Member 2:
+4
2
-4
2
q3
q4
q6
q5
d4 = -1.538x10-3
d3 = -9.433x10-3
d6 = 1.863x10-3
d5 = -0.01
q3
q4
q6
q5=
-6.0 kNm
3.75 kN
20.0 kNm
0.25 kN
0.25 kN
6.0 kNm
3.75 kN
4 kN
2
10 mm253 2 kN2 kN
2
[FEF]
8 m
0.75
0.75
-0.1875
12/82
2
-0.75
4
0.75
-0.75
-0.75
-0.1875
0.1875
0.75
2
-0.75
4
3 45
63
4
5
6
8
200200=
20 kNm
4 kN0.6 kN/m
BC
20 kNm
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8 m 4 m 4 m
2EI EIA
C
10 mm
Deflected
Curve
0.6 kN/m
18 m
8.55 kN
43.19 kNm
3.75 kN
6.03 kNm
V(kN)
x (m)+
8.55
3.75
-0.25
0.25 kN
6.0 kNm
3.75 kN
4 kN
2
20 kNm
M
(kNm) x (m)
-43.19
621
+
-
20
D3 = -9.433 mm
D6
= +1.863x10-3 radD4
= -1.538x10-3 rad
D5 = -10 mm
Example 6
Internal Hinges
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77
30 kN
A CB
EI2EI
4 m 2 m
9kN/m
Hinge
2 m
For the beam shown, use the stiffness method to:(a) Determine all the reactions at supports.
(b) Draw the quantitative shear and bending moment diagrams
and qualitative deflected shape.
E= 200 GPa,I= 50x10-6 m4.
C2EI EI
43
2
3 4
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[K] = EI1
2
1 2
0.0
0.0
1.0
2.0
AC
B4 m 2 m 2 m
1 21
[k]1 =EI
2EI
2EI
EI
3 1
3
1
[k]2 =0.5EI
1EI
1EI
0.5EI
2 4
2
4
Use 2x2 stiffness matrix,
i j
MiMj
[ ]
=LEILEI
LEILEIk
/4/2
/2/422
30 kN
9kN/m
Hinge
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79
0.0
0.0
D1
D2
15 kNmB C
15 kNm30 kN
2
12 kNm
A B
12 kNm 9kN/m
1[FEF]
= EI1
2
1 2
0.0
0.0
1.0
2.0
D1
D2
=
0.0006 rad
-0.0015 rad
-12
15
+
Global matrix:
A C
B
1 2
43
12 kNm 15 kNm1
2
12 kNm12 kNm 9kN/m3
1
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80
Member 1:
q3
q1
12
-12+=
EI
2EI
2EI
EI
3 1
3
1
18
0.0=
d3
d1
= 0.0
= 0.0006
A B1[FEF]A
B
1
18 kNm22.5 kN 13.5 kN
A B
9 kN/m
1
CB
415 kNm
B C15 kNm 30 kN
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81
B C
30 kN
22 2
q2
q4
= -0.0015
= 0.0
d2
d4
15
-15+=
0.5EI
1EI
1EI
0.5EI
2 4
2
4
0.0
-22.5
=
Member 2:
22.5 kNm
20.63 kN9.37 kN
22.5 kNmB C
30 kN
A B
9 kN/m
9.37 kN13.5 kN
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30 kN
A CB
EI2EI
4 m 2 m
9kN/m
Hinge
2 m
-20.63
V(kN)x (m)
22.59.37
-13.5
+
2.5 m
M
(kNm)x (m)
-18
10.13
-22.5
18.75
+
-
+-
-
BL= 0.0006 radBR= -0.0015 rad
13.5 kN22.5 kN 20.63 kN9.37 kN18 kNm 22.87 kN
Example 7
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83
20 kN
A CBEI2EI
4 m 4 m
9kN/m
Hinge
For the beam shown, use the stiffness method to:(a) Determine all the reactions at supports.
(b) Draw the quantitative shear and bending moment diagrams
and qualitative deflected shape.
E= 200 GPa,I= 50x10-6 m4.
2
2 EI EI 6
7
4
5
4
5
6
7
1 3
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84
A CB1
0.375
0.375
1.0
-0.75
-0.75 2.0
0.0
0[K] = EI
1
2
3
1 2 3
0.5625
[k]1 =
0.75EI
EI
-0.75EI
2EI/L
0.375EI
0.75EI
0.75EI
-0.375EI
2EI
0.75EI
EI
-0.75EI
-0.75EI
- 0.375EI
0.375EI
-0.75EI
4 5 1 2
4
5
1
2
0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
[k]2 =
0.1875EI
-0.375EIEI
0.375EI - 0.1875EI
0.1875EI
0.375EI
0.5EI
-0.375EI
EI
1 3 6 7
1
3
6
7
2
20 kN
A C
B9kN/m
5
20 kN
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85
Q1 = -20
Q3 = 0.0
Q2 = 0.0
D1
D3
D2
18
0.0
-12+
D1
D3
D2 =
-0.02382 m
0.008933 rad
-0.008333 rad
[FEM]
12 kNmA B
12 kNm
18 kN18 kN
1
9kN/mA CB
1 2
6
7
4 2 EI EI
Global:
= EI
1
2
3
1
0.5625
0.375
-0.75
2
-0.75
2.0
0.0
3
0.375
0
1.0
12 kNm
18 kN
1
2
3
2EI1
24
5
12 kNmA B
12 kNm
1
9kN/m
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86
A B1 [FEF] 18 kN18 kN
+12
18
-12
18
Member 1:
q4
q5
q1
q2
=
0.75EI
EI
-0.75EI
2EI/L
0.375EI
0.75EI
0.75EI
-0.375EI
2EI
0.75EI
EI
-0.75EI
-0.75EI
- 0.375EI
0.375EI
-0.75EI
4 5 1 2
4
5
1
2
= 0.0
= 0.0
= -0.02382
= -0.00833
d5
d4
d2
d1
=107.32
44.83
0.0
-8.83
A B
107.32 kNm
8.83 kN
44.83 kN
9kN/m
1
CB
2
EI1
3
6
7
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Member 2:
CB 3
44.66 kNm
B C
11.16 kN11.16 kN
2
+0
0
0
0
= -0.02382
= 0.008933
= 0.0
= 0.0
d3
d1
d7
d6
q1
q3
q7
q6
0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
=
0.1875EI
-0.375EIEI
0.375EI - 0.1875EI
0.1875EI
0.375EI
0.5EI
-0.375EI
EI
1 3 6 7
1
3
6
7
=0.0
-11.16
-44.66
11.16
20 kN
9kN/m
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A CB
4 m 4 m
V(kN)x (m)
44.83
8.83
-11.16-11.16
+
-
M(kNm)
x (m)
-107.32
-44.66-
-
A B107.32 kNm
8.83 kN44.83 kN
9kN/m
144.66 kNm
B C
11.16 kN11.16 kN
2
BL= -0.008333 rad BR= 0.008933 rad
Example 8
F th b h th tiff th d t
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89
30 kN
A C
BEI
2EI
4 m 2 m
9kN/m
Hinge
40 kNm
2 m
For the beam shown, use the stiffness method to:(a) Determine all the reactions at supports.
(b) Draw the quantitative shear and bending moment diagrams
and qualitative deflected shape.
40 kNm at the end of memberAB. E= 200 GPa,I= 50x10-6 m4.
A C2EI EI
1 2
433 4
1
2
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90
[K] = EI1
2
1 2
0.0
0.0
1.0
2.0
B4 m 2 m 2 m
1 2
[k]1 =EI
2EI
2EI
EI
3 1
3
1
[k]2 =0.5EI
1EI
1EI
0.5EI
2 4
2
4
1
Use 2x2 stiffness matrix: i jMiMj
[ ]
=
LEILEI
LEILEIk
/4/2
/2/422
3
30 kN
A C
EI2EI
9kN/m
Hinge
40 kNm40 kNm
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91
15 kNmB C
15 kNm30 kN
2
12 kNm
A B
12 kNm 9kN/m
1[FEM]
Global matrix:
A C
B
1 2
43
1
2
12 kNm 15 kNm
BEI2EI 40 kNm
Q1 = 40
Q2 = 0.0
D1
D2
-12
15
+
D1
D2=
0.0026 rad
-0.0015 rad
= EI1
2
1 2
0.0
0.0
1.0
2.0
40 kNm
12 kNm
A B
12 kNm 9kN/m
1[FEF]A 1
3
1
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92
A B1[FEF]AB
1
40 kNmA B38 kNm
9 kN/m
1.5 kN37.5 kN
Member 1:
38
40
=q3
q1
= 0.0
= 0.0026
d3
d1
12
-12
+=EI
2EI
2EI
EI
3 1
3
1
CB
2
4
2
15 kNmB C
15 kNm 30 kN
2
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93
2 2
Member 2:
q2
q4
= -0.0015
= 0.0
d2
d4
15
-15
+=0.5EI
1EI
1EI
0.5EI
2 4
2
4
0.0
-22.5=
22.5 kNmB C
30 kN
20.63 kN9.37 kN
9.37 kN
1.5 kN
7 87 kN
40 kNmA B
38 kNm
9 kN/m
1 5 kN37 5 kN
22.5 kNmB C
30 kN
20 63 kN9 37 kN
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94
30 kN
A CB
4 m 2 m
9kN/m
Hinge
40 kNm
2 m
-20.63
V(kN)x (m)
37.5
9.371.5+
M
(kNm)x (m)
-38
40
-22.5
+
-
18.75
+--
BL= 0.0026 radBR=- 0.0015 rad
7.87 kN38 kN m 1.5 kN37.5 kN 20.63 kN9.37 kN
Example 9
For the beam shown, use the stiffness method to:
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95
20 kN
A CB
EI2EI
4 m 4 m
9kN/m
Hinge40 kNm
For the beam shown, use the stiffness method to:(a) Determine all the reactions at supports.
(b) Draw the quantitative shear and bending moment diagrams
and qualitative deflected shape.
40 kNm at the end of memberAB. E= 200 GPa,I= 50x10-6 m4
20 kN
EI2EI
9kN/m
Hinge40 kNm
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96
A C
B1 2
6
7
4
5
1
2
3
A CBEI2EI
4 m 4 m
Hinge40 kN m
12 kNm
18 kN
12 kNm
18 kN
9 kN/m
1[FEM]
i j j
Mi
i
Vj
Mj
Vi
[ ]
=
LEILEILEILEI
LEILEILEILEI
LEILEILEILEI
LEILEILEILEI
k
/4/6/2/6
/6/12/6/12
/2/6/4/6
/6/12/6/12
22
2323
22
2323
44
1 22A C
B
6
7
4
5
6
7
4
5
1
2 EI EI 1
2
3
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97
[K] = EI
1
2
3
1 2 3
0.5625
0.0
0
0.375
0.375
1.0
-0.75
-0.75
2.0
[k]1 =
0.75EI
EI
-0.75EI
2EI
0.375EI
0.75EI
0.75EI
-0.375EI
2EI
0.75EI
EI
-0.75EI
-0.75EI
- 0.375EI
0.375EI
-0.75EI
4 5 1 2
4
5
1
2
0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
[k]2 =0.1875EI
-0.375EIEI0.375EI - 0.1875EI
0.1875EI
0.375EI0.5EI
-0.375EI
EI
1 3 6 7
1
3
6
7
75
20 kN
EI
9kN/m
40 kNm
20 kN
40 kNm
1
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98
Q1 = -20
Q3
= 0.0
Q2 = 40
D1
D3
D2
18
0.0
-12+
D1
D3
D2 =
-0.01316 m
0.0049333 rad
-0.002333 rad
A C
B1 2
64 2 EI EI
12 kNm
18 kN
12 kNm
18 kN
9 kN/m
1[FEF]
= EI
1
2
3
1 2 30.5625
0.0
0
0.375
0.375
1.0
-0.75
-0.75
2.0
12 kNm
18 kN
Global:
1
2
3
1
12
1
2EI4
5
12 kNm
18 kN
12 kNm
18 kN
9 kN/m
1[FEF]12 kNm
18 kN
12 kNm
18 kN
1
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99
1
2EI
[q]1
+12
18
-12
18
q4
q5
q1
q2
=
0.75EI
EI
-0.75EI
2EI
0.375EI
0.75EI
0.75EI
-0.375EI
2EI
0.75EI
EI
-0.75EI
-0.75EI
- 0.375EI
0.375EI
-0.75EI
4 5 1 2
4
5
1
2
=87.37
49.85
40
-13.85
Member 1: [q]1 = [k]1[d]1 + [qF]1
13.85 kN
40 kNm87.37 kNm
49.85 kN
= 0.0
= 0.0
= -0.01316= -0.002333
d5
d4
d2
d1
22 C
B
1
3
EI 6
7
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100
Member 2: [q]2 = [k]2[d]2 + [qF]2
+0
0
0
0
q1
q3
q7
q6
0.375EI
0.375EI
-0.1875EI
0.5EI
-0.375EI
-0.375EI
=
0.1875EI
-0.375EIEI
0.375EI - 0.1875EI
0.1875EI
0.375EI
0.5EI
-0.375EI
EI
1 3 6 71
3
6
7
=0.0
-6.18
-24.696.18
24.69 kNm
6.18 kN6.18 kN
= -0.01316
= 0.004933
= 0.0
= 0.0
d3
d1
d7
d6
22
[q]2
20 kN
A CEI2EI
9kN/m 40 kNm
BL= -0.002333 rad BR = 0.004933 rad
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101
A CB4 m 4 m
24.69 kNmB C
6.18 kN6.18 kN
A B
87.37 kNm 13.85 kN49.85 kN
40 kNm
M(kNm)
x (m)
-
-87.37
+40
--24.69
BL 0.002333 rad BR 0.004933 rad
49.85
-6.18
V(kN)x (m)
-6.18-
13.85+
Fixed-End Forces (FEF)
- Axial- Bending
Temperature Effects
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102
Bending
Curvature
Tm> TR
Thermal Fixed-End Forces (FEF)
Tt
bt TTT+=
Tt F
AFF
BF
)(tand
T
d
TT tb =
=
Room temp = TR
ctd
TR
NA
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103
Tl
2mT =
Tb > Tt BF
BMF
AM
Rmaxial TTT = )(
tbbending TTT = )(
)()(d
TyTy
=
y
A
A B
axialaxial
A B
y
y
TR Tm
Tt
Tb
Tb - Tt
cbd
- Axial
axialaxial
F
TtT > T
TR Tm
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104
A B
F
AFF
BF
dAFA
axial
F
A =
dAE axial=
dATE axial = )(
axialTEA )(=
AETTF RmAF
axial )()( =
dATE axial= )(
Tb > Tt
Tm> TR
Rmaxial TTT = )(
- Bending
y
y
)()(
d
TyTy
=
y Tt
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105
A B
y
dAyMA
y
F
A =
dATyE y = )(
dAd
TyyE
= )(
= dAydTE 2)(
EId
TTF ulA
F
bending )()(
=
F
BMF
AM
dAyE=
tbbending TTT = )(
y
Tb
O
d
)()( dd
Elastic Curve: Bending
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106
ds
dx
After
deformation
d
Before
deformation
y dx
ds = dx y
)()( ddx =
)( dy )(1
dx
d
=
Bending Temperature
dx
Tt
Tb
Tl > Tu
O
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107
dxd
Tyyd )()(
=
dxd
Td )()(
=
Tb
Tt
yy
dT
y
Tl > Tu
Tu
d
2
bt
m
TT
T
+
= d
MM
Tb
cb
ct
Tt
T= Tb- Tt
d
T=
EI
M
d
T
dx
d=
== )(
1)(
Example 10
For the beam shown, use the stiffness method to:(a) Determine all the reactions at supports.
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108
A CB
EI2EI
4 m 4 m
T2 = 40oC
T1 = 25oC
182 mm
(b) Draw the quantitative shear and bending moment diagrams
and qualitative deflected shape.
Room temp = 32.5oC, = 12x10-6 /oC,E= 200 GPa,I= 50x10-6 m4.
A CB
EI2EI
T2 = 40oC
T1 = 25oC
182 mm
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109
12 3
1 2
Mean temperature = (40+25)/2 = 32.5
Room temp = 32.5oC
FEM+7.5 oC
-7.5 oC
a(T /d)EI19.78 kNm = 19.78 kNm
4 m 4 m
mkNEId
TFFbending =
=
= 78.19)502002)(
182.0
2540)(1012()2)(( 6
12 3
A C
BEI2EI1 2
19.78 kNm19.78 kNm
182 mm
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110
[M1] = 3EI1 + (1.978x10-3)EI
0
Element 1:
M1
M2
q1
q2
[q] = [k][d] + [qF]
+1.978
-1.978(10-3)EI=
1
2
2
1
2 1
2
1EI
Element 2:
M3
M1
q3
q1
+0
0
=0.5
1
1
0.5
1 3
1
3
EI
1= -0.659x10
-3 rad
4 m 4 m
12 3
A C
B
EI2EI1 2
19.78 kNm19.78 kNm
182 mm
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111
Element 2:
M3
M1
q3
q1
= +0
0
0.5
1
1
0.5
1 3
1
3EI
= -0.659x10-3
= 0
=6.59 kNm
-26.37 kNm
= -0.659x10-3
= 0=
-3.30 kNm
-6.59 kNm
Element 1:
M1
M2=
q1
q2+
19.78
-19.78
1
2
2
1
2 1
2
1EI
4.95 kN4.95 kN
26.37 kNm 6.59 kNm
A B
6.59 kNm 3.3 kNm
B C
2.47 kN2.47 kN
4 m 4 m
A CB
4 m 4 m
+7.5 oC
-7.5o
C 3.3 kNm
26.37 kNm
4.95 kN 2.47 kN 2.47 kN
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112
4 m 4 m
M
(kNm)x (m)
26.37
6.59
-3.30
+
-
V(kN) x (m)
-4.95-2.47
- -
B= -0.659x10-3 radDeflected
curve x (m)
Example 11
For the beam shown, use the stiffness method to:(a) Determine all the reactions at supports.
(b) Draw the quantitative shear and bending moment diagrams
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113
A CB
EI,AE2EI, 2AE
4 m 4 m
T2 = 40oC
T1 = 25oC
182 mm
(b) Draw the quantitative shear and bending moment diagrams
and qualitative deflected shape.
Room temp = 28 oC, a = 12x10-6 /oC,E= 200 GPa,I= 50x10-6 m4,
A = 20(10-3
) m2
A
CB
EI2EI
4 m 4 m
T2 = 40oC
T1 = 25oC 1
2 3
7
8
9
1 2
4
5
6
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114
4 m 4 m
Element 1:
mkNm
mkNm
L
AE/)10(2
)4(
)/10200)(1020(2)2( 62623
==
mkN
m
mmkN
L
EI=
=
)10(20
)4(
)1050)(/10200(24)2(4 34626
mkNm
mmkN
L
EI=
=
)10(10)4(
)1050)(/10200(22)2(2 34626
kNm
mmkN
L
EI)10(5.7
)4(
)1050)(/10200(26)2(63
2
4626
2 =
=
mkNm
mmkN
L
EI/)10(75.3
)4(
)1050)(/10200(212)2(12 33
4626
3=
=
A CB
EI,AE2EI, 2AE
4 m 4 m
T2 = 40oC
T1 = 25oC
182 mm
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115
Fixed-end forces due to temperatures
Mean temperature(Tm) = (40+25)/2 = 32.5oC,
TR = 28 oC
4 m 4 m
mkNEId
TFFbending =
=
= 78.19)502002)(
182.0
2540)(1012()2)(( 6
19.78 kNm19.78 kNm
432 kN432 kN
A B
+12 oC
-3 oC
kNmkNmAETFFaxial 432)/10200)(310202)(285.32)(1012()(2626 ===
A CB
EI,AE2EI, 2AE
4 m 4 m
T2 = 40oC
T1 = 25oC
182 mm
1
2 3
7
8
9
1 2
4
5
6
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116
FEM
+12 oC
-3 oC
19.78 kNm
A B
19.78 kNm
432 kN432 kN
Element 1:
[q] = [k][d] + [qF]
0
0
0
d1
d2
d3
q4
q6
q5
q1
q2q3
=
4
5
6
1
2
3
4 1
- 2x106
0.00
0.00
2x106
0.00
0.00
2
0.00
-3750
-7500
0.00
3750
-7500
3
0.00
7500
10x103
0.00
-7500
20x103
2x106
0.00
0.00
-2x106
0.00
0.00
5
0.00
3750
7500
0.00
-3750
7500
6
0.00
7500
20x103
0.00
-7500
10x103
432
-19.78
0.00
-432
0.00
19.78
+
4 m 4 m
A CB
EI,AE2EI, 2AE
4 m 4 m
T2 = 40oC
T1 = 25oC
182 mm
1
2 3
7
8
9
1 2
4
5
6
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117
Element 2:
[q] = [k][d] + [qF]
d1
d3
d2
0
0
0
0
0
0
0
0
0
+
q1
q3
q2
q7
q8q9
- 1x106
0.00
0.00
1x106
0.00
0.00
0.00
-1875
-3750
0.00
1875
-3750
0.00
3750
5x103
0.00
-3750
10x103
1x106
0.00
0.00
-1x106
0.00
0.00
0.00
1875
3750
0.00
-1875
3750
0.00
3750
10x103
0.00
-3750
5x103
7 8 91 2 3
=
1
2
3
7
8
9
A CB
EI,AE2EI, 2AE
4 m 4 m
T2 = 40oC
T1 = 25oC
182 mm
1
2 3
7
8
9
1 2
4
5
6
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118
D1
D3
D2 =
0.000144 m
-719.3x10-6
rad
-0.0004795 m
Q1 = 0.0
Q3 = 0.0
Q2 = 0.0
D1
D3
D2
-432
19.78
0.0+=
1
2
3
1
3x106
0.0
0.0
2
0.0
5625
-3750
3
0.0
-3750
30x103
Global:
Element 1:
0
0
0
q4
q5
4
5
6
4 1
- 2x106
0.00
0 00
2
0.00
-3750
7500
3
0.00
7500
10 103
2x106
0 00
0.00
5
0.00
3750
7500
6
0.00
7500
20 103
432
19 78
0.00
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119
= 144x10-6
= -479.5x10-6
= -719.3x10-6
0
d1
d2
d3
q6
q1
q2q3
=6
1
2
3
0.00
2x106
0.00
0.00
-7500
0.00
3750
-7500
10x103
0.00
-7500
20x103
0.00
-2x106
0.00
0.00
7500
0.00
-3750
7500
20x103
0.00
-7500
10x103
-19.78
-432
0.00
19.78
+
=
q4
q6
q5
q1
q2q3
144.0 kN
-23.38 kNm
-3.60 kN
-144.0 kN
3.60 kN
9.00 kNm
A B 1
2 3
4
5
6
A B144 kN
3.60 kN
23.38 kNm
144 kN
3.60 kN
9 kNm
= 144x10-6
= -479.5x10-6
719 3 10 6
Element 2:
d1
d
d2
0
0
0
q1
q2
- 1x106
0.00
0 00
0.00
-1875
3750
0.00
3750
5 103
1x106
0 00
0.00
0.00
1875
37500
0.00
3750
10 103
7 8 91 2 3
1
2
3
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120
= -719.3x10-6
144 kN
-9 kNm
-3.6 kN
-144 kN
3.6 kN
-5.39 kNm
=
q1
q3
q2
q7
q8q9
B C 7
8 9
1
2
3
144 kNB C
3.60 kN
9 kNm
144 kN
3.60 kN
5.39 kNm
d3
0
0
0
0
0
0
0
+q3
q7
q8q9
=0.00
1x106
0.00
0.00
-3750
0.00
1875
-3750
5x103
0.00
-3750
10x103
0.00
-1x106
0.00
0.00
37500
0.00
-1875
3750
10x103
0.00
-3750
5x103
3
7
8
9
A CB
EI2EI
4 m 4 m
T2 = 40oC
T1 = 25oC
Isolate axial part from the system
RCRA
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121
RA RA=RC
+
Compatibility equation: dC/A = 0
RA = 144 kN
RC = -144 kN
0)4)(285.32(1012)4(
2
)4( 6 =++ E
R
E
R AA
A CB
EI2EI
4 m 4 m
T2 = 40oC
T1 = 25oC
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122
A B
144 kN
3.60 kN
23.38 kNm
144 kN
3.60 kN
9 kNm
144 kN
B C3.60 kN
9 kNm
144 kN
3.60 kN
5.39 kNm
V(kN)x (m)
-3.6
-
M
(kNm) x (m)
23.38
8.98
-5.39
+
-
D3 = -719.3x10-6 radDeflected
curve x (m)
D2= -0.0004795 mm
Skew Roller Support
- Force Transformation
- Displacement Transformation- Stiffness Matrix
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123
j
x
y
Displacement and Force Transformation Matrices
4
5
6
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124
m
i
j
m
i
j
x
y
1
2
3
4
5
6
yx
1
2
3
x y
j
y
x
45
6
y
x
Force Transformation
yx qqq coscos 5'4'4 =
xy qqq coscos 5'4'5 =
6'6 qq =
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125
i
yx
1
2
3
m
i
j
x
y
1
2
3
4
5
6
xx ijx
=yy ij
y
=
66 qq
6
5
4
q
q
q
=
100
0
0
xy
yx
6'
5'
4'
q
q
q
=
6'
5'
4'
3'
2'
1'
6
5
4
3
2
1
1000000000
0000
000100
00000000
q
q
q
q
xy
yx
xy
yx
[ ] [ ] [ ]'qTq T=
y
d4
d4cos
x
x
x
Displacement Transformation
4
5
6j4
5
6x y
yx ddd coscos' 544 +=
xy ddd' coscos 545 +=
66' dd =
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126
x
y
yx
x
y
xd4c
osy
y
d5
x
y
d5cos
x
d5co
sy
j66
6'
5'
4'
d
d
d
=
100
0
0
xy
yx
6
5
4
d
d
d
=
6
5
4
3
2
1
6'
5'
4'
3'
2'
1'
1000000000
0000
000100
00000000
dd
d
d
dd
dd
d
d
dd
xy
yx
xy
yx
[ ] [ ][ ]dTd ='
[ ] [ ] [ ]'qTq T=
[ ] [ ][ ][ ]
)'( FT
qd'k'T +=
[ ] [ ][ ] [ ] [ ]FTT qTd'k'T '+=
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127
[ ] [ ] [ ][ ][ ] [ ] [ ] [ ][ ] [ ]FFTT qdkqTdTk'Tq +=+= '
[ ] [ ] [ ][ ]TkTkTherefore T ', =
[ ] [ ] [ ]FTF qTq '=
[ ] [ ] [ ]'qTq T=
[ ] [ ][ ]dTd ='
[ ] [ ] [ ][ ]TkTk T '=
i j
ji 4*
5*6*
1*
2*3* 1
Stiffness matrix
i j
4
56
1
2
3
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128
ix = cos i
iy= sin i
jx= cos j
jy= sin j
[q*] = [T]T[q]
*6
5*
*4
*3
2*
*1
q
q
q
q
=
100000
00000000
000100
0000
0000
jxjy
jyjx
ixiy
iyix
1 4 5 62 3
1*
2*
3*
4*5*
6*
[ T]T
6'
5'
4'
3'
2'
1'
q
q
q
q
[ ]
=000100
0000
0000
ixiy
iyix
T
1 4 5 62 3
1
2
3
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129
[ ]
=
100000
0000
0000
jxjy
jyjx
T
4
5
6
[ ]
=
LEILEILEILEI
LEILEILEILEI
LAELAE
LEILEILEILEI
LEILEILEILEI
LAELAE
k
/4/60/2/60
/6/120/6/120
00/00/
/2/60/4/60
/6/120/6/120
00/00/
'
22
2323
22
2323
1
3
4
6
2
5
1 2 3 4 5 6
[ k] = [ T]T[ k ][T] =
Ui
Vj Mj
- iy6EI
L2
Ui Vi Mi
- iy6EI
L2
Uj
AE
L- ixiy)(
12EI
L3
AE
Lixjx
+12EI
L3iyjy)-(
AE
Lixjy
-12EI
L3iyjx)-()(
AE
Lix
2 +12EI
L3iy
2
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130
Vi
Mi
Uj
Vj
Mj
ix6EI
L2
2EI
L
jy6EI
L2
- jx6EI
L2
4EI
L
ix6EI
L2
4EI
L
jy6EI
L2
jx6EI
L2-
2EI
L
AE
Liy
2 +12EI
L3ix
2)(
ix6EI
L2
ix6EI
L2
AE
L
iyjx-
12EI
L3ixjy)-(
jy6EI
L2
AE
L
jx2 +
12EI
L3
jy2)(
jy6EI
L2
jx6EI
L2-
AE
L
- jxjy)(12EI
L3
- jx6EI
L2
AE
L- ixiy)(
12EI
L3
- iy6EI
L2
- iy6EI
L2
AE
L
ixjx+
12EI
L3iyjy)-(
AE
Liyjy
+12EI
L3ixjx )-(
AE
Liyjy
+12EI
L3ixjx)-(
12EI
L3jx
2)
AE
L- ( ixjy- iyjx)
12EI
L3
AE
Liyjx
-12EI
L3ixjy)-(
AE
L- jxjy)(
12EI
L3
AE
Ljy
2 +(
Example 12
For the beam shown:
(a) Use the stiffness method to determine all the reactions at supports.
(b) Draw the quantitative free-body diagram of member.
(c) Draw the quantitative bending moment diagrams
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131
40 kN
4 m4 m 22.02 o
(c) Draw the quantitative bending moment diagrams
and qualitative deflected shape.
TakeI= 200(10
6
) mm
4
, A = 6(10
3
) mm
2
, andE= 200 GPa for all members.Include axial deformation in the stiffness matrix.
40 kN
4 m4 m 22.02o
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132
40 kN40 kNm
20 kN
40 kNm
20 kN
[ qF ]
[FEF]
1Global
i j
1
i j
Local
20sin22.02=7.5
20cos22.02=18.54
1
2
3
4
5
6
4
5
6
x*
x1*
2*3*
ix = cos 0o = 1,
iy= cos 90o = 0 jx= cos 22.02o = 0.9271,jy = cos 67.98
o = 0.3749
22.02 o
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1
i j1
2
3
4
5
6
Local
Local stiffness matrix
i j ji ji
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134
[k]1 = 103
1
23
4
5
6
1 4 5 62 3
-150.0
0.000
0.000
150.0
0.000
0.000
0.000
-0.9375
-3.750
0.000
0.9375
-3.750
0.000
3.750
10.00
0.000
-3.750
20.00
150.0
0.000
0.000
-150.0
0.000
0.000
0.000
0.9375
3.750
0.000
-0.9375
3.750
0.000
3.750
20.00
0.000
-3.750
10.00
[ ]
=
LEILEILEILEI
LEILEILEILEI
LAELAE
LEILEILEILEILEILEILEILEI
LAELAE
k
/4/60/2/60
/6/120/6/120
00/00/
/2/60/4/60/6/120/6/120
00/00/
22
2323
22
2323
66
Mi
Vj
Mj
Vi
Nj
Ni
Stiffness matrix [k]:
1
1 4 5 62 3
-150.0 0.000 0.000150.0 0.000 0.000
x*
x1
4
5
6
1*
2*3* 1
i j1
2
3
4
5
6
Global Local
4
5
6
2*
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135
[k]1 = 103
1
2
3
4
5
6
0.000
0.000
150.0
0.000
0.000
-0.9375
-3.750
0.000
0.9375
-3.750
3.750
10.00
0.000
-3.750
20.00
0.000
0.000
-150.0
0.000
0.000
0.9375
3.750
0.000
-0.9375
3.750
3.750
20.00
0.000
-3.750
10.00
Stiffness matrix [k*]: [ k* ] = [ T]T[ k ][T]
[k*]1 = 103
4
56
1*
2*
3*
4 1* 2* 3*5 6
-139.0
0.351
1.406
129.0
1.406
51.82
-56.25
-0.869
-3.750
51.82
21.90
-3.476
0.000
3.750
10.00
1.406
-3.476
20.00
150.0
0.000
0.000
-139.0
-56.25
0.000
0.000
0.9375
3.750
0.351
-0.869
3.750
0.000
3.750
20.00
1.406
-3.750
10.00
x*
x1
4
5
6
1*
2*3*
4 m4 m 22.02 o
40 kN
x*
x4
5
6
2*
40 kN40 kNm
40 kNm [ F ]
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136
Global Equilibrium:
Q1 = 0.0
Q3 = 0.0
D1*
D3*=
36.37x10-6 m
0.002 rad
[Q] = [K][D] + [QF]
= 1031*
3*
1*
129
1.406
3*
1.406
20.0
D1*
D3*
-7.5
-40+
20 kN
40 kNm
20 kN
[ qF ]
20sin22.02=7.5
20cos22.02=18.54
4 m4 m 22.02 o
40 kN
x*
x1
4
5
6
1*
2*3*
40 kN 40 kNm40 kNm
4
5
6
2*
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137
Member Force : [q] = [k*][D] + [qF]
0
40.0
20
-7.54
18.54
-40.0
+
q4
q6
q5
q1*
q2*q3*
= 103
4
5
6
1*
2*
3*
4 1* 2* 3*5 6
-139.0
0.351
1.406
129.0
1.406
51.82
-56.25
-0.869
-3.750
51.82
21.90
-3.476
0.000
3.750
10.00
1.406
-3.476
20.00
150.0
0.000
0.000
-139.0
-56.25
0.000
0.000
0.9375
3.750
0.351
-0.869
3.750
0.000
3.750
20.00
1.406
-3.750
10.00
0
0
0
36.4x10-6
02x10-3
-5.06
60
27.5
0
13.48
0
=
40 kN
13.48 kN
60 kNm
27.5 kN
5.06 kN
7.518.5420 kN
4 m4 m 22.02 o
40 kN
5.05 kN27.51 kN
60.05 kNm
13.47 kN
40 kN
50 04
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138
+
Bending moment diagram(kNm)
Deflected shape
50.04
-
-60.05
0.002 rad
Example 13
For the beam shown:
(a) Use the stiffness method to determine all the reactions at supports.
(b) Draw the quantitative free-body diagram of member.
(c) Draw the quantitative bending moment diagrams
d lit ti d fl t d h
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139
40 kN
22.02o
8 m 4 m 4 m
2EI, 2AE EI,AE
6 kN/m
and qualitative deflected shape.
TakeI= 200(106) mm4, A = 6(103) mm2, andE= 200 GPa for all members.
Include axial deformation in the stiffness matrix.
40 kN
22.02o
8 m 4 m 4 m
2EI, 2AE EI,AE
6 kN/m
mkN
m
mkNm
L
AE
=
=
3
262
10150
)8(
)/10200)(006.0(
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140
1 21
2
3
4
5
6
7*
8*9*
Global
21
2
3
4
56
11
2
3
4
5
6
Local
mkN10150
mkN
mmmkN
LEI
=
=
3
426
1020
)8()0002.0)(/10200(44
mkNL
EI
=3
1010
2
kN
m
mmkN
L
EI
3
2
426
2
1075.3
)8(
)0002.0)(/10200(66
=
=
mkN
m
mmkN
L
EI
/109375.0
)8(
)0002.0)(/10200(1212
3
3
426
2
=
=
1 21
2
3
4
5
6
7*
8*9*
GlobalLocal : Member 1
6 3 3 6
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[k]1
= [k]1
= 2x103
4
5
6
12
3
4 1 2 35 6
-150.0
0.000
0.000
150.0
0.000
0.000
0.000
-0.9375
-3.750
0.000
0.9375
-3.750
0.000
3.750
10.00
0.000
-3.750
20.00
150.0
0.000
0.000
-150.0
0.000
0.000
0.000
0.9375
3.750
0.000
-0.9375
3.750
0.000
3.750
20.00
0.000
-3.750
10.00
14
5
1
2
[ q
]11
2
4
5
[ q]
[q] = [q]
Thus, [k] = [k]
1 21
2
3
4
5
6
7*
8*9*
23
x7 *
8*9*[ q* ] 2
3
4
56
[ q ]
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Member 2: Use transformation matrix, [q*] = [T]T[q]
q1
q3
q2
q4
q5
q6
q1
q3
q2
q7*
q8*q9*
0.9271
0.3749
-0.3749
0.9271
0
0
0
0
0
0
0
0
0
0 0
0
0
1
1
0
0
1
=
1
2
3
7*
8*
9*
1 4 5 62 3
0 0
0
0
1
0
0
0
0
0
0
0
0
0
ix = cos 0o = 1,iy = cos 90
o = 0 jx = cos 22.02o = 0.9271,
jy = cos 67.98o = 0.3749
21
x*
7*21 4
Stiffness matrix [k]:
1
1 4 5 62 3
-150.0 0.000 0.000150.0 0.000 0.000
21
23
x*
x7*
8*9*[ q* ]
21
2
3
4
56
[ q ]
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[k]2 = 103
2
3
4
5
6
0.000
0.000150.0
0.000
0.000
-0.9375
-3.7500.000
0.9375
-3.750
3.750
10.000.000
-3.750
20.00
0.000
0.000
-150.0
0.000
0.000
0.9375
3.7500.000
-0.9375
3.750
3.750
20.000.000
-3.750
10.00
Stiffness matrix [k*]: [k*] = [T]T[k][T]
[k*]2 = 103
1
2
3
7*
8*
9*
1 7* 8* 9*2 3
-139.0
0.351
1.406
129.0
1.406
51.82
-56.25
-0.869
-3.477
51.82
21.90
-3.476
0.000
3.750
10.00
1.406
-3.476
20.00
150.0
0.000
0.000
-139.0
-56.25
0.000
0.000
0.9375
3.750
0.351
-0.869
3.750
0.000
3.750
20.00
1.406
-3.477
10.00
1 21
2
3
4
5
6
7*
8*9*
1
2
3
4
5
6
8*
4
5
4 1 2 35 6
-150.0
0 000
0.000
0 9375
0.000
3 750
150.0
0 000
0.000
0 9375
0.000
3 750
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[k]1= 2x103
5
61
2
3
0.000
0.000150.0
0.000
0.000
-0.9375
-3.7500.000
0.9375
-3.750
3.750
10.000.000
-3.750
20.00
0.000
0.000
-150.0
0.000
0.000
0.9375
3.7500.000
-0.9375
3.750
3.750
20.000.000
-3.750
10.00
[k*]2 = 103
1
2
37*
8*
9*
1 7* 8* 9*2 3
-139.0
0.351
1.406
129.0
1.406
51.82
-56.25
-0.869
-3.477
51.82
21.90
-3.476
0.000
3.750
10.00
1.406
-3.476
20.00
150.0
0.000
0.000
-139.0
-56.25
0.000
0.000
0.9375
3.750
0.351
-0.869
3.750
0.000
3.750
20.00
1.406
-3.477
10.00
32 kNm32 kNm
6 kN/m
40 kN6 kN/m
1 21
2
3
4
5
6
7*
8*
9*
1
2
3
4
5
6
8*
40 kN40 kNm
40 kNm40 kNm
40 kNm32 kNm
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Global:
=
-509.84x10-6 rad
18.15x10-6 m
0.00225 rad
58.73x10-6 m
D3
D1
D9*
D7*
0
0
0
0 +-32 + 40 = 8
0
-40
-7.5
D3
D1
D9*
D7*
24 kN24 kN
1
= 1030
0
-139
450
10
1.40660
0
1.406
1.406
-139
129
0
101.406
20
1 3 7* 9*
1
37*
9*
7.5
18.5420 kN
7.5
Member 1: [ q] = [k][d] + [qF]
4 1 2 35 6
32 kNm
24 kN
32 kNm
24 kN
6 kN/m
114
5
6
1
2
3
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0
32
24
0
24-32
+
0
0
0
d1=18.15x10-6
0d3=-509.84
x10-6
q4
q6
q5
q1
q2q3
= 2x103
45
6
1
23
4 1 2 35 6
-150.0
0.000
0.000
150.0
0.0000.000
0.000
-0.9375
-3.750
0.000
0.9375-3.750
0.000
3.750
10.00
0.000
-3.75020.00
150.0
0.000
0.000
-150.0
0.0000.000
0.000
0.9375
3.750
0.000
-0.93753.750
0.000
3.750
20.00
0.000
-3.75010.00
-5.45 kN
21.80 kNm
20.18 kN
5.45 kN
27.82 kN
-52.39 kNm
=
q4
q6
q5
q1
q2q3
6 kN/m
5.45 kN
20.18 kN
21.80 kNm5.45 kN
27.82 kN
52.39 kNm
21
3
x*
x7*
9*
1 7* 8* 9*2 3
20sin22.02=7.5
20cos22.02=18.54
40 kN40 kNm
20 kN
40 kNm
20 kN
[ qF ]
2
2 8*
Member 2: [ q] = [k][d] + [qF]
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q1
q3
q2
q7*
q8*q9*
=103
12
3
7*
8*
9*
-139.0
0.351
1.406
129.0
1.40651.82
-56.25
-0.869
-3.750
51.82
21.90-3.476
0.000
3.750
10.00
1.406
-3.47620.00
150.0
0.000
0.000
-139.0
-56.250.000
0.000
0.9375
3.750
0.351
-0.8693.750
0.000
3.750
20.00
1.406
-3.75010.00
0
40
20
-7.5
18.54
-40
+
18.15x10-6
-509.84x10-6
0
58.73x10-6
0
0.00225
q1
q3
q2
q7*
q8*q9*
-5.45 kN
52.39 kNm
26.55 kN
0 kN
14.51 kN
0 kNm
= 5.45 kN
26.55 kN
52.39 kNm
14.51 kN
40 kN
5.45 kN
26.55 kN
52.39 kNm
14.51 kN
40 kN6 kN/m
5.45 kN
27.82 kN
52.39 kNm
5.45 kN
20.18 kN
21.80 kNm
40 kN6 kN/m21.80 kNm
14.51cos 22.02o
=13.45 kN
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22.02o
8 m 4 m 4 m
5.45 kN
20.18 kN 14.51 kN54.37 kN
3.36 m
M
(kNm) x (m)
53.81
-21.8
-
V(kN)
x (m)
26.55
+
20.18
+- -
-27.82
-52.39
-
12.14 +
-13.45