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P. 105

action.  For  example,  for  the  deflections  and  moments
          we obtain

                 For a distributed load the summation should be replaced
          by the integral.

                      n    P                   n  P
                                           z 
              y (x y )    3 i   1   x  i   ;  M   i   2   x  i   .
                     i 1 8  EJ z             i 1 4


          8.4 Short beams on elastic foundation

                 In the calculation of short beams it is convenient to use
          the method of initial parameters. While any number of sites, this
          method allows the constant integrations to express in terms of the
          initial parameters y , ,  M and Q - the deflection, the rotation
                            0   0    0      0
          angle, the moment and the transverse force at the origin.
          We write the solution of equation (8.3) in the form

                 y    x   AK   x   BK   x   CK   x   
                           1          2           3
                                                                    (8.25)
                         DK   x   y x  *    ,
                             4
          where A , B ,C , D   -  constants,  which  are  determined  from  the
          boundary  conditions  of  the  problem;  -  A.N.Krylov’s  functions
          that have the form
                   K    chx    x   cos  ; x 
                    1
                            1
                   K   x    ch x sin x   sh x  cos x  ;
                    2
                            2
                            1                                       (8.26)
                   K   x   sh x sin  ; x 
                    3
                            2
                            1
                   K    x    ch x sin x   sh x cos  . x 
                    4
                            2
                 Krylov’s rule of function differentiation is schematically
          shown in Fig. 8.5. The arrow in the diagram indicates where the
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