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Tips for shear force and bending moment diagram

  1. For concentrated or point load, SFD is rectangular (uniform) and BMD is triangular (linear).
  2. For uniformly distributed load, SFD is triangular and BMD is parabolic.
  3. For uniformly varying load, SFD will be parabolic and BMD will be cubic. 
  4. If the algebraic sum of moments on the beam is zero and no other forces are acting then reactions are zero and SFD is a straight line.
  5. If there is a vertical ordinate or sudden jump in a BMD, it indicates concentrated moment at that point whose magnitude is equals to length of the ordinate.
  6. At fixed end, bending moment is always zero, until an concentrated moment not there.


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