1. Mx, My, Mz , Nz, Qx, Qy. , , , , , ( ). , , . , , , , . . , , .
, D (. 5.34, ). , , ( ). , , Mx, My, Mz , Nz, Qx, Qy .
, , , : , , , - .
:
- Nz , ;
- Mz , ;
- Qx , y ( Qy - , x);
- Qx Qy ;
- x y .
(0 £ z 1 £ a).
. 5.34, . . x y , . 5.34, . z 1 . N , .. , : S z = 0; Nz = 0. å x = 0 x = 0 (. 5.35, ).
z , , (. 5.35,):
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S mz = 0; z = 0.
Qx Qy :
S x = 0, Qx - P = 0, Qx = P = 1 ;
S y = 0, Qy = 0.
Qx (. 5.35, ) , 1, . :
S My = 0, y + × z = 0, y = - P × z.
My z:
z = 0, My = 0; z = a, My = - P × a = -1×0,3 = -0,3 ×.
, My , My .
C (0 £ z 2 £ b).
. 5.34, e. . x y , . 5.34, . z 2 . , . , - , . Nz, Mz , Qx, Qy , Mx My - (. 5.34, e):
S z = 0, Nz = 0; S Mz = 0, Mz + P × a = 0, Mz = - P × a = -0,3 ×.
(. 5.35, ).
S x = 0, Qx - P = 0, Qx = P = 1 .
Qx . 5.35, .
S y = 0, Qy - q z = 0; Qy = q z;
z = 0, Qy = 0; z = 0,6 , Qy = 2×0,6 = 1,2 .
Qy . 5.35 .
Mx .
z = 0, Mx = 0; z = 0,6 , Mx = -0,36 ×;
= 2 z = 0; z = 0- Mx z = 0.
, , . xy, . 5.34, : x , Mx
. 5.35
(. 5.35, ).
S My = 0, My + P z = 0, My = - P z;
z = 0, My = 0; z = 0,6 , My = -0,6 ×.
My - . - .
CD (0 £ z 3 £ c 1).
. 5.34, . . x y , . 5.34, . z 3 D. , , (. 5.34, ):
S z = 0, N - P = 0, N = P = 1 ;
S Mz = 0, ×.
Mz - . :
S x = 0, Qx + q b 1 = 0, Qx = - q b 1 = -2×0,6=-1,2 .
Qx - Qx.
S y = 0, Qy = 0;S Mx = 0, Mx + P b 1 = 0, Mx = - P b 1 = -0,6 ×.
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Mx - . - .
S My = 0, My + P a - q b 1 z 3 = 0, My = q b 1 z 3 - P a = 1,2 z 3 - 0,3.
My z 3. z 3 = 0; My = -0,3 ×. , - .
z 3 = 0,5 My = 1,2×0,5 - 0,3 = 0,6-0,3 = 0,3 ×.
My (. 5.35, ).
2. . . My Qx , . Mx, My , Qx , Qy Mx , . D Mx My , Qx , N Mz , .
3. N, Mx, My Mz ( Qx Qy ). . My , (. 5.35, ) , . :
16,7×103 /2,
Wy = =1,8×10-5 3.
. Mx My , , . :
×,
:
/2=33,32 ,
:
3 .
, :
,
Wp - . ,
Wp = 2 W = 2×2,1×105 3 = 4,2×105 3,
=7,143 .
D. Mx My , , D. N :
/2 = 0,555 ,
F = b × c = 0,06×0,03=0,0018 2 - ;
66666 /2 = 66,67 ,
3.
My :
/2 = 16,67 .
, :
/2 = 27,07 ,
WK = b× c 3 = 0,493×0,033 = 13,3×10-6 3 - , . b - , ( b / c = 2, b = 0,493).
4. R = 180 . :
.
. (t = 0), :
, R = 180 .
. :
36,25 < 180 .
D. N, Mx My :
.
0. :
< 180 .
, t = 27,7 . :
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;
< 180 .
, , .