Page 42 - Mechanical Engineer's Data Handbook
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STRENGTHS OF  MATERIALS                                                           31

          CW  111: M,,=  WR  (A to B)                 Simply supported  beam, beam mass only
          Stresses as for case I.
                                                        157
                                                     f=+@qi
          Deflection in direction of  load               L

          Deflection in direction normal

                         to load &=p(Rf+RL+:) El   2
                                                      Built-in beam, mass of  beam only













                                                      Concentrated  mass: for all cases with  a  single mass
                                                     r=&a


                                                      where: y = static deflection at load,  g = acceleration
                                                      due to gravity.
                                                      For cantilever mass at end f= 1J2nJ3EI/mL3






          I A.6   Transverse vibration of beams
          Formulae are given for the fundamental frequency of
          transverse vibrations of  beams due to the beam’s own   Simply supported  beam, central  mass
          mass and due to concentrated masses.
                                                      f = 1 J2nJzZ3z
          Ungorm cantilever, beam mass only
          Frequency of  vibration f = - fi
                              0.56
                               L2
         where: m=mass  per unit length of  beam, I=second
          moment of  area, L=length  of  beam.

                                                      Simply supported  beam, non-central  mass

                                                     f= 1/2nJz&m
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