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If the distributed load q terminates earlier in the cross-section
where we determine y or  , it should be continued to the
proposed cross-section, while adding a compensating load. For
example, for a beam, shown in fig. 6.19 general equation of
deflections has the form
R x 3  q x b  4  q x c  4
EJ y   x  EJ y  EJ  x  1   .
z z 0 z 0 b c
6 24 24

The geometric initial parameters are determined from the
boundary conditions (conditions of beam fixing) (fig. 6.20):
- at the beginning of coordinates the beam is hard fixed (fig.
6.20, a)   0y  0 ,   0  0 ;
- at the beginning of coordinates there is a hinge support (fig.
6.20, b)   0y  0 ,   0y l  ;

- at the beginning of coordinates there is a free end of the beam
(fig. 6.20 c)   a  ,  y a l  0 .
y
0

Figure 6.20

6.10 Calculation for hardness

In some cases, the beams that meet the strength condition, do
not have sufficient hardness, i.e., their binding rafters are too large
(those that exceed the established norm). Therefore, despite the

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