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following checks. In the first attempt, you can use the calculation
of the strength of both the straight beam
M
  max   ,

max
W
and then increased slightly gained size, strength check timber
considering its curvature by the formula (4.7). Overloading
should not exceed 5%.

4.3 Calculation of the displacement curves in uneven
bars

0
In general, flat bend when M  , N  and Q  ,
0
0
determination of angular and linear displacement curves in the
most convenient to carry out energy bars by Mora. For large
curvature beams moving in terms of its axis has the form

M M N N MN  NM Q Q
1P 
  1 ds   1 ds   1 1 ds k  1 ds ,
н
s ES R s EF s EFR s GF
(4.9)

where M , N and Q - expressions of internal force factors
caused by a given load, M , N and Q - expressions of internal
1 1 1
force factors caused the unit load that is applied in the direction
of the desired movement.
For beams of low curvature influence the longitudinal and shear
force is usually neglected, and consider that S R  J , then the
н z
formula (4.9) greatly simplifies and takes the form

M M
  1 ds . (4.10)
1P 
s EJ z

When the expressions for the internal forces are different for
different parts of the crooked timber, it is necessary to calculate
Mora’s integrals for individual sites and the results are
summarized. To determine the angular displacement required in
section, angle of which is determined, attach unit dummy

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