In this video, Sign Convection for SF & BM, Important Points for Drawing SFD and BMD & Point of Contra flexure is explained in following Timestamps:

0:00 - Mechanics of Solids lecture series
0:27 – Outlines on the session
0:57 – Sign convection for shear force
3:23 – Sign convection for bending moment
5:31 – Important points for drawing shear force and bending moment diagram
8:08 – Point of contra flexure

Following points are covered in this video:

Examples based on thermal stresses including yielding of support
1. Sign convection for shear force
2. Sign convection for bending moment
3. Important points for drawing shear force and bending moment diagram
4. Point of contra flexure

Engineering Funda channel is all about Engineering and Technology. Here this video is a part of Mechanics of Solid/ Engineering Mechanics.

#EngineeringFunda, #MechanicsOfSolids, #SignConvection, #ShearForceDiagram, #BendingMomentDiagram, #SFD, #BMD, #PointOfContraflexure

Details of Sign Convection for SF & BM:

In structural analysis, sign conventions are used for shear force (SF) and bending moment (BM) to indicate the direction and sense of the internal forces and moments developed in a beam. The following are the commonly used sign conventions for SF and BM:

Shear Force Sign Convention:

Positive shear force (upward direction): When the external loads acting on the beam tend to create a clockwise rotation of the beam section to the left of the section being considered.

Negative shear force (downward direction): When the external loads acting on the beam tend to create a counterclockwise rotation of the beam section to the left of the section being considered.

Bending Moment Sign Convention:

Positive bending moment (concave upward): When the external loads acting on the beam tend to create a sagging or concave upward deformation of the beam.

Negative bending moment (concave downward): When the external loads acting on the beam tend to create a hogging or concave downward deformation of the beam.

In other words, the positive shear force and bending moment cause upward deflection and concave upward deformation of the beam, while the negative shear force and bending moment cause downward deflection and concave downward deformation of the beam.

It is important to note that the sign conventions for SF and BM may vary depending on the coordinate system and the orientation of the beam. Hence, it is important to use a consistent sign convention throughout the analysis and design of the structure.