Steps to discover zero shear, max bending moment & point of Contraflexture
This construction video will teach you in detail how to discover zero shear ,maximum bending moment & point of Contraflexture.
If the Shear becomes zero, it signifies that the forces are either zero or nullifying each other. It produces bending moment at constant, because it is the product of force with distance. On the other hand, shear refers to the rate of change of bending moment.
Different methods can be applied to work out point of zero shear or maximum bending moment. In this construction video, the most convenient method is explained.
In a bending beam, Point of the Contraflexture denotes a point the value for bending moment is 0 i.e. a location where no bending takes place. In a bending moment diagram, it refers to the point where the bending moment curve meets with the zero line.
Alternatively stated, where the bending moment adjusts its sign from negative to positive or vice versa. Flexural reinforcement may be decreased at this point.
So, sufficient amount of reinforcement should spread away from the point of contraflexure to produce bond strength and to enable shear force transfer.