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terms concentrated moment M that is located at a distance a
M
from the left end of the beam, will be multiplied by the multiplier
0
x a M equal to one. Thus, the equation of bending moments
will have the form
M x a 0 P x a p 1 q x a q 2
M x M P x M ,
z 0 0 a p a q a
0! 1! 2!
M
where a , a , a – abscissas of points of applying in respect
M P q
with the concentrated moment M , concentrated force P and
points of beginning of the action of the distributed load q .
Present the resulting expression in generalized form:
M , if k 0;
k
x a
M x M P x , where P , if k 1;
z 0 0 a
! k
q , if k 2.
We write the differential equation of beam curved axis and
integrate it twice (perform the integration without opening
brackets):
x a k
EJ y M P x ,
z 0 0 a
! k
P x 2 x a k 1
EJ x M x 0 C , (6.39)
z 0 a
2 (k 1)!
M x 2 P x 3 x a k 2
EJ y x 0 0 Cx D . (6.40)
z a
2 6 (k 2)!
We see that x : C EJ 0 EJ – angle of rotation of
0
z z 0
a cross-section at the origin (in units of hardness);
D EJ y 0 EJ y – beam deflection at the origin.
z z 0
So, universal equations for the angles of rotation of the beam
deflection are as follows:
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