Page 108 - 4560
P. 108

Q    x   4y  3 K EJ   4  2  K EJ   4M  K 
                                z
                            2
                       0
                                      0
                                                     0
                                                          4
                                           3
                                               z
                             3
                            d y *    x
                       Q K        .
                      0  1       3
                              dx
                 A  partial  solution  (8.27)  at  different  external  loads
          assumes different shapes.
                 While acting the centered moment  M (Figure 8.6) at the
          distance  a from the origin
                           M
                                                         a
                                   
                 y *    x    K     x a   , when  x  .
                                 3 
                                            
                          2 EJ  z
                 While  acting  the  centered  moment  P   at  the  distance
          b from the origin
                           P
                 y *    x    K    x b   , when  x  .
                                                        b
                                            
                                 4 
                          3 EJ  z
                 While acting the uniformly distributed load of intensityq ,
          which begins in the section  x 
                                         c
                         q
              y *   x       1 K   1     x c     , when  x  .
                                                            c
                                              
                      4 4 EJ
                             z
                 On the  left end of the  beam the two primary options of
          four  are  always  known.  The  others  are  determined  from  the
          boundary conditions at the other end of the beam.
                 For example, if the left end of the beam is rigidly fixed,
          then y  ;   .
                           0
                   0
                0       0
                 If  the  left  end  of  the  beam  is  hingedly  dropped  up
                            0
                   0
          then y  ;  M  .
                0        0
                 If the left end is not fixed and is free from concentrated
          loads, then M  ; Q  .
                          0
                                   0
                       0       0
                 If on the left end of the beam the concentrated loads   M
                                                                         л
                                               0
          and  P  are applied, then M  ;Q  .
                                       0
                л                   0      0

          Questions for self-assessment

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