ECIV 320 Structural Analysis I Internal Loadings in Structural Members Sections 4.1 – 4.5 Study all examples
Internal Loading in Structural Members Axial Loading PPP
Internal Loading in Structural Members P M V Flexure
Internal Loading in Structural Members Internal Loadings represent the resultant of stresses distributed over the cross section
Sign Convention P
Internal Loadings at Specified Point - PROCEDURE Support Reaction May need to be calculated before Internal Loadings Cut the Member Pass Section parpendicular to its axis at the specified point Attention: Keep all distributed loadings moments and forces in their exact location.
Internal Loadings at Specified Point-PROCEDURE Free Body Diagram Hint: Draw FBD of segment with the least number of loads Hint: Indicate Resultants in Positive Directions
Internal Loadings at Specified Point-PROCEDURE Equations of Equilibrium Hint: Sum moments at the section about centroid Hint: Numerical Results (+) FBD OK, (-) Internal Loadings Opposite Direction
EXAMPLE
Example
Shear and Moment Functions for Beams Design ! Variations of internal Shear and Moment along Axis Normal Force is usually ignored Exception: Compressive Axial Forces (Buckling) Pay attention to discontinuities of applied loads Use same approach as before but with variable location of section
Shear and Moment Functions for Beams
Example EXAMPLE
Shear & Moment Diagrams for Beams Variations of V and M in a graph Form
Shear & Moment Diagrams for Beams