L1 = 6.0
L2 = 4.0
H = 8.0
= 2
q = 1 /
I1 : I2 =2:3
E = const
1. .
, , :
n = 3 = 5 3 = 2
.. .
2. .
1 2
3. :
δ11Χ1 + δ12Χ2 + Δ1 = 0,
δ21Χ1 + δ22Χ2 + Δ2 = 0.
4. .
.
Σ X = 0, X1 HD = 0, HD = 1
Σ Y = 0, VE + VD = 0, VD = 0
Σ D = 0, X2 L1 -VE L2 = 0,
VE = 1,5
Σ X = 0, HD = 0,
Σ Y = 0, VE + X1 - VD = 0,
VD = 2,5
Σ D = 0,
Σ X = 0, q H + P HD = 0,
HD = 10 ()
Σ Y = 0, VE - VD = 0,
VD=10 ()
5. .
δ11 = = 88 82 + 868 =
= + =
δ12 = = - 668 = - δ21 = δ12 = -
δ22 = = 66 6 + 64 6 =
= + =
Δ1 = = 8 32 8 + 8 6 32 +
+ 4 4 40 + (728 + 4566 +440) =
= + + + =
Δ2 = = - 6632 + 64 40 =
= + = -
6. .
S = 1 + 2
δSS = = 88 82 + 64 6 +
+ (88 + 455 + 22) = + + =
S δi j = δ11 + δ12 + δ21 + δ22 = - - + =
δSS = S δi j, .. , , .
7.
( ).
ΔS = = 832 8 + 5632 +
+ 6 4 40 + (404 + 6456 +728) + 44 40
= + + + + =
S Δi = Δ1 + Δ2 = - =
S Δi = ΔS .. , , .
|
|
8. :
896/(3EI) Χ1 - 144/(3EI) Χ2 + 4704/(3EI) = 0,
-144/(3EI) Χ1 + 120/(3EI) Χ2 - 256/(3EI) = 0.
8/(3EI), :
112 Χ1 - 18 Χ2 + 588 = 0,
-18 Χ1 + 15 Χ2 - 32 = 0.
112 -18
D0 = = 11215 - 1818 = 1356
-18 15
-588 -18
D1 = = -58815 + 1832 = - 8244
32 15
112 -588
D2 = = 11232 - 18588 = - 7000
-18 32
1 = D1 / D0 = -8244 / 1356 = - 6,080 ()
2 = D2 / D0 = -7000 / 1356 = -5,162 ()
, .. 1 2 :
112(-6,080) 18(-5,162) + 588 = -588,004 + 588 = 0,004 0
- 18(-6,080) +15 (-5,162) - 32 = 32,01 - 32 = 0,01 0
.. .
9.
= 11 + 22 +
10.
) :
S = 0, 16,64 - 16,64 = 0
S = 0, -23,36 + 14,322 + 9,028 = 0
) :
Δ1 = = - (00 + 4416,32 + 16,648)-
- 861,154 + 4/6(15,684 + 4619,52 +23,368)+
+ 15,684 4 = (-262,827-18,464 +239,36 +41,913)=
= (-281,291 + 281,273) = 0
: -0,018100% /-281,291 = 0,006 % .
Δ2 = = (016,64 + 431,154-14,3326) +
+ 9,0284 6 = ( -24,048 +24,075) = 0
: 0,027100% / 24,075 = 0,11 % .
, ,
.
11.
S = 0,
-16,64 + q84 - 8 = 0,
= 1,92 ()
S = 0,
= 6,08 ()
S = 0, - + q8 = 0, 0 = 0
S = 0,
-V6 +14,332 +16,64 =0,
V = 5,162 ()
S = 0,
-V6 +14,332 +16,64 =0,
V = 5,162 ()
S Y = 0, V + V = 0, 0 = 0
S = 0, 9,028 - V4 = 0
V = 2,257 ()
S = 0, 9,028 V4 = 0
V = 2,257 ()
S Y = 0, -V + V = 0, 0 = 0
S = 0,
-23,36 + D8 - з4 = 0
D = 3,92 ()
S D = 0,
-23,36 - 8 + з4 = 0
= -1,92 () , .
S = 0, -D + + = 0, 0 = 0
:
|
|
12. () N, :
S = 0, N + 1,92 = 0
N = -1,92 ()
, N
, .. .
S Y = 0, -N + 5,162 = 0
N = -1,92 ()
S Y = 0,
ND - 5,162 + 2,257 = 0
ND = -2,905 () .
S Y = 0,
N - 1,92 + 1,92 = 0
N = 0
N :
13. M, N, Q .
S F = 0, -V3 + H8 - q 84 - 4 - VD3 +HD8 -VE7 = 0,
-5,1623 + 6,088 -184 - 24 - 2,9053 +3,928 - 2,2577 = 0,
0 = 0, , , M, N, Q .
.
1. .
2.
.
3.
.
4. .
5.
.
.
6.
.
7.
.
8. .
9. , .
10. .
11. .
12. M, N, Q.
1. - , 4 (210297 ).
2. , .
3. () .
4. 0,001.
5. .
1
Ω | |||||
Z1 | Z2 | ||||
hl | l/2 | l/2 | |||
hl/2 | l/3 | 2l/3 | |||
hl/3 | l/4 | 3l/4 | |||
| hl (n+1) | l (n+2) | (n+1)l (n+2) | ||
| 2hl/3 | 3l/8 | 5l/8 |