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P. 129

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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