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– position of the neutral line does not depend on the magnitude
and sign of force P ;
– neutral line intersects the coordinate axes at the points that
belong quadrant opposite to where the pole;
– farther from the origin placed pole, the center of gravity closer
to the neutral line section is;
– if the pole is placed on the main central axis, the neutral line
perpendicular to this axis;
– if the pole moves along a certain line, the neutral line revolves
around a point.
Major tensions arise at points of cross-section of the most
remote from the neutral axis (fig. 1.8). Conditions strength is:
 P  e e 
    max p    1 2 y y  2 z z K     ; p

K
K
 F  i z i y 

 (1.20)
 P  e y e z 
    max c  F  1 i 2 y  i 2 z B     , c

В
B

   z y 
where y , z and y , z – coordinates of points K and B .
K K B B
According to formula (1.19) we consider two partial cases.
Thus, if e  e  0, then the neutral line is located at infinity,
y z
which corresponds to the central tension (compression) and when
it will pass through e  e   the center of gravity of the cross-
y z
section corresponding to bending.

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