Beams and frames Flashcards
What can beams be made out of?
Timber, concrete or steel
What are beams used in?
Buildings and small bridges
What are frames?
Beams connected to one another by rigid joints
How do rigid joints work?
Rigid joint prevents relative rotation of connected members at the joint
What are the internal forces involved in beams and frames?
horizontal force N
vertical force V
bending moment M
What does action-reaction mean?
For every action, there is an equal and opposite reaction
What does N stand for?
Axial force
What does V stand for?
Shear force
What diagrams can be obtained from beam and frame analysis?
- Axial force diagram
- Shear force diagram
- Bending moment diagram
What are the unknowns in beams and frames?
Reactions and internal forces
When is the beam or frame statically determinate?
If all the reactions can be determined using the equations of equilibrium
What is the shear force?
The shearing force (SF) is defined as the algebraic sum of all the transverse forces acting on either side of the section of a beam or a frame.
When is a bending moment considered positive?
A bending moment is considered positive if it tends to cause concavity upward (sagging).
When is a bending moment considered negative?
If the bending moment tends to cause concavity downward (hogging), it will be considered a negative bending moment
