I.
1. (. 5.25)
S y = 0, R 0 + q × c - P = 0, R 0 = - q × c + P = -10×1,4 + 12 = -2 ;
S M 0 =0, ,
M 0 = q c (b + 0,5 c) - M - P (b + c + e) = 10×1,4×(1,8 + 0,5×1,4) -
- 20 - 12×(1,8 + 1,4 + 1,2) = -37,8 ×.
. 5.25
:
å MD = 0, M 0 + R 0×4,4 + q × c ×(0,5× c + e) + M = -37,8 - 2×4,4 +
+ 10×1,44×(0,5 1,4 + 1,2) + 20 = 46,6 - 46,6 = 0.
.
2. . (5.23), :
E Ix y (z) = E Ix y 0 + z + -
- + .
M 0 Q 0 - (.. ). ½ z > a , , , z > a - z £ a. : y 0 = 0; j0 = 0; M 0 = -37,8 ×, R 0 =
= -2 ( ). :
E I y (z) = - - +
+ .
:
=-37,8× z - z 2 + - +
+ 20×(z - 3,2) .
yD j D:
×3.
×2.
= 2×108 /2 :
×2.
, :
D , .
II.
. 5.26
1. (. 5.26).
S M 0 =0, RB (b + c + e) - q ×(c + e)×[ b + 0,5×(c + e)] + M + P b = 0,
= ;
S MB =0, R 0 (b + c + e) - 0,5× q ×(c + e)2 - M + P ×(c + e) = 0,
.
y:
S y =0; R 0 + RB + P - q (c + e) = 7,86 + 14,14 + 8 - 10×3 = 30 - 30 = 0.
.
2. . , :
z = 0 : y 0 = 0; 0=0.
, :
.
j0. z = b + c + e , y = 0. , j0:
.
E I j0 = -20,84 ×2. :
.
, :
.
yD j D:
H×3.
×2.
( = 2×108 /2):
×2.
, ,
.
D , .
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