Axial and bending stresses Flashcards
What is the function of a structure?
The function of any structure is to support external loads and uses internal forces to resist external loads and support further by using foundations
Where is the load from structures transferred to?
The foundations
How are the loads and stresses distributed in cables?
They are subjected to tension and load transferred to a column
How are broadcasting masts made stable?
By cables in tension
How are suspension bridge loads distributed and made stable?
Their loads are transferred to the cables and then the foundation
What are the components of a truss?
Struts and ties
How can uniform stress distribution be denoted?
P/A
What are the sign conventions for tension and compression?
Tension: +
Compression: -
Why is it desirable to have a uniform stress distribution in structural elements?
- If you have non-uniform stress distributions, some spots experience high stress, creating stress concentration. Some elements won’t be holding an equal amount of load
- Every portion of the member would be evenly stressed and the material would be utilized most efficiently.
How is strain denoted?
ε= x/L
How deformation in structures?
Using micro-strains
How can materials be identified?
Each material has a unique stress-strain behaviour - Young’s Modulus (measures stiffness)
What can be said about brittle materials and their stress and deformation?
- Brittle materials have a smaller yield stress
- Brittle materials experience little deformation
What is axial stress?
Axial stress is the normal force acting on the surface divided by the surface area
What is a longitudinal strain?
Longitudinal strain is the strain in the direction of the applied force
True or false, strains are large and non-reversible?
True
How is the load applied on beams?
Load is applied perpendicular to its longitudinal axis
How does a beam sustain loads?
A beam sustains loads mainly through bending action
What does UDL stand for?
Uniformly distributed load
What are the different types of load-supported beams you can have?
- Simply-supported beam
- Cantilevered beam
- Simply supported with cantilever end
- Continuous beam
Where are the fibers in compression during a sagging moment?
On the top end
Where are the fibers in compression during a hogging moment?
At the bottom end
What assumptions need to be made before performing these calculations?
a) Material is linear-elastic
b) Material is isotropic
c) Plane sections remain plane
What is the internal moment?
The internal moment is the moment of resistance
