21 terms

Structures and Forces

here are some notes on the science unit of structures and forces
Causes of Forces
large collisions create big forces and smaller collisions create smaller forces
live load - a load that is always changing
dead load - a load that never changes
Tension, Compression, Bending, Torsion, and Shear
Stable Structures
a structure that is less likely to tip, it is also a key when designing a structure
more stable = wide & low
Spin Stabilization is also a good way of keeping stable
lowest support of a structure
Unbalanced Structures
a structure that has more weight on 1 side then the other
to make a unstable structure into a stable structure you can use cables, put some dead load on the other side or make it symmetrical and have about the same amount af weight of both sides
Types of Ground Foundations
Pilings - large metal, concrete or wood cylinder that is dug into the bedrock
for a road: the making of a solid layer
Smooth asphalt then the Rough asphalt then the Crush then the Gravel
Designing with Forces
you want to distribute the load throughout the structure. no part of the structure to have to carry to much
you also want to direct the forces along angled components so that the forces hold in sued of pull aport
you also want to shape the part to withstand forces that will likely happen
How Structures Fail
lever-changes the amount of force needed on
effort force-a downward force
load force-an upward force
Tension Force
Compression Force
Torsion Force
Bending Force
Shear Force
Stable Loads on a Structure
move the load through out the structure with brace, arch and cantilever
Light but Stable Structures
to make a structure light but stable use I beams, L beams and T beams
Internal Forces, External Forces or Stresses
internal forces - forces acting on the inside of a structure, can cause failure
external forces - forces acting on the outside of the structure, causes internal forces to act upon the structure
Particles in Materials of a Structure
steel - strong forces pulling on its particles in regular arrangement
graphite - particles attract strongly in some directions and almost not at all in others
rubber particles attracts many particles in all directions
Using Frictional Forces
force of friction resists movement between two surfaces that rub together.
Flying Buttresses
columns on the outsides of a structure that connect to the building near the top and are used to support the outer walls in much the same way that two sides of an arch support each other.
Car bumpers are designed to buckle in a collision - as the metal fails, it absorbs some of the energy of the impact, which protects the occupants of the vehicle. Blades of grass on a sports field buckle as players land, which absorbs some of the impact forces on the players body.