Sign Conventions for Beams
Shear Force:
If the force is upwards to the left of the section, then it is positive shear
force. Similarly, if the force is downwards to the right side of the
section, then it is negative shear force, as illustrated in above figure.
Shear Force:
If the force is upwards to the left of the section, then it is positive shear
force. Similarly, if the force is downwards to the right side of the
section, then it is negative shear force, as illustrated in above figure.