Forces, Strengths And Properties of Materials Flashcards
What are the two types of forces that can act on a structure?
static forces and dynamic forces
Explain what static forces are?
A static force is a force that does not move.
Explain what dynamic forces are.
A dynamic force on a structure is caused when something moving strikes the structure.
Give an example of a static and dynamic force.
Static force: A hanging light is a static force on the ceiling.
Dynamic force: A person jumping on a trampoline.
What are loads on a structure?
The forces acting on some structures are the weights of things such as motor vehicles, water, parts of buildings.
What are the different types of loads ?
There are two types of loads, even and uneven loads.
What are the different types of forces?
- Tension (tensile) force
- Compression (compressive) force
- Torsion (twisting) force
- Shear (tearing) force
What effect do the different forces have on structures?
- tension force is a pulling force. It tends to stretch the members of structures it acts on.
- compression force presses or pushes on structures.
- torsion force tends to twist members of structures.
- shear force tends to slide past other objects.
What is internal cross-bracing?
Members. That are added inside the frames of towers and other structures to brace them.
What are the four cross sectional shapes that beams are made of?
- I beam section
- channel section
- square-tube section
- T-bar section
What is the formula used to work out density?
Density= Mass (divide) volume
What is density?
The density of a material is the mass of a cubic meter of that material.
Name one example of a structure that is made of a low-density material.
The wheels of high performance cars.
What is hardness?
Hardness s a measure of how a material resists other materials making holes into its surface.
In industry, how is the hardness of a material tested.
With a Brinell hardness tester.
What is a flexible material?
A flexible material is one that can bend easily without breaking.
What is a brittle material?
A brittle material is a very stiff material that will break without first bending.
What are factors that affect corrosion of iron?
- water accelerates corrosion.
- moisture is necessary for corrosion of iron.
- acid greatly accelerates corrosion
- salt greatly accelerates corrosion
What can you do to prevent corrosion?
- use special paint that prevents corrosion.
- corrosion can be prevented for a while by galvanizing the iron
- corrosion can be prevent by using metals that do not corrode in the place of iron.
- hot-dip galvanizing
- non-corroding non-metals such as plastics and wood can be used in the place of iron or steel.
What are the four cross sectional shapes that beams are made of?
- I beam section
- channel section
- square-tube section
- T-bar section
What is the formula used to work out density?
Density= Mass (divide) volume
What is density?
The density of a material is the mass of a cubic meter of that material.
Name one example of a structure that is made of a low-density material.
The wheels of high performance cars.
