Normal Stress and Strains

17/11/2025

Examples of internal forces

• axial force

• shear force

• bending moment

Axial force

The force that acts on the axis causing tension or compression

The internal force that maintains the equilibrium along the axis of the beam (ie the algebraic sum of all forces acting parallel to the axis of the beam to one side of the cross section)

Shear force

the internal force that acts parallel to a surface on once side of the surface causes a friction like effect on the object

the internal force that maintains equilibrium in the direction orthogonal to the axis of the beam (ie the algebraic sum of all forces acting perpendicular to the axis of the beam to one side of the cross section)

Bending moment

internal moment maintaining equilibrium (ie the algebraic sum of all moments about the section acting to one side of the section