1. In a bending beam, a point is known as a point of contraflexure if it is a location at which no bending occurs (where bending moment changes its sign).
2. In a bending moment diagram, it is the point at which the bending moment curve intersects with the zero line.
3. In other words, where the bending moment changes its sign from negative to positive or vice versa. Knowing the place of the contraflexure is especially useful when designing reinforced concrete or structural steel beams and also for designing bridges.

Procedure to locate the point of contra-flexure in bending beam:

• First always find the support reaction of beam.
• Find the shear force at all the important location of beam.
• Find the bending moment at all important location of beam.
• After drawing the bending moment diagram, we come to know about bending moment changes its sign from negative to positive or vice versa.
• Now locate the distant x from one end of the beam to the region where bending moment changes it sign from negative to positive or vice versa. And Calcuate the bending moment from the considered end of beam to that region of beam where bending moment comes zero or changes it's sign.
• Equate that bending moment general expression to zero, so that the value of 'x' can be determined.