Structures

Types of Structures

Natural structures

@@Natural structures are formations that occur in nature without human intervention.@@

%%They can be found in various forms such as mountains, caves, canyons, rivers, and even living organisms.%%

Manufactured structures

^^Manufactured structures are a human-made formation^^

They are mostly found as buildings, some examples are bridges, tunnels, towers, and buildings.

What Is A Structure?

%%A structure is an object with a definite shape and size which serves a purpose%%

Frame structures

A structure in which a skeleton of materials supports the weight of the other parts

@@Examples: most buildings, ladders, bicycle frame@@

Shell structures

^^A completely hollow structure that keeps its shape examples^^

==Examples: Canoe, igloo, helmet==

Mass structures

A structure built by pilling up or forming similar materials on top of each other. They rely on the size and weight of the materials they are made up of and can resist strong forces

Describing Structures

Function

  • Most structures have more than one purpose or function
  • A structure should be able to support their weight along with the weight of their loads

Structure Values

Aesthetics

Bilateral Symmetry - structures that can be cut into two identical halves. Examples: Chairs, the human brain, t-shirts, etc.

Radial Symmetry - parts that are arranged around a center core. Examples: Pizza, starfish, umbrellas, etc.

Safety

Margin of Safety - the need for a structure to perform as expected for a long time so people’s safety isn’t at risk

Materials

The properties of the materials must match the purpose of the structure. Example: A high-rise building should be able to withstand strong winds and earthquakes so they may make it out of steel compared to wood.

There are three main types of materials that are commonly used in the manufacturing of various products. These are:

1. Composite Materials

Composite materials are made up of two or more different materials that are combined to create a new material. Some examples of composite materials include fiberglass, carbon fiber, and Kevlar.

2. Layered Materials

Layered materials are made up of multiple layers of the same or different materials that are stacked on top of each other. Some examples of layered materials include paper, cardboard, and laminates.

3. Woven and Knit Materials

Woven and knit materials are made up of interlocking fibers that are woven or knitted together to create a fabric. Some examples of woven and knit materials include cotton, wool, and silk.

When deciding on materials, there are several factors to consider. These include:

Cost

  • Cheaper materials may wear out quickly or require lots of maintenance

Appearance

  • The material should be aesthetically pleasing and fit with the overall design of the projects

Environmental Impact

  • Using recycled materials or materials made from renewable resources can help preserve Earth’s resources which puts an overall good impact on the environment

Energy Efficiency

  • The choice of materials can reduce the amount of energy a structure needs
  1. Buildings need to be kept warm in the winter
  2. Refrigerators and freezers require electricity to keep food cold

Joints

A fastening that holds parts of a structure together

Rigid Joint

Joints that do not allow movement because it is fused together (Skull, wooden beams, etc.)

Mobile Joints

Joints that allow movements (Door hinges, elbows, etc.)

Types of Rigid Joints

The following are the types of rigid joints:

  1. Fasteners:
    • Fasteners are used to connect two or more materials.
    • Examples of fasteners include bolts, screws, nails, and rivets.
  2. Interlocking Shapes:
    • Carefully shaped parts that can hold themselves together
    • Examples of interlocking shapes include Legos
  3. Ties:
    • Ties are typically strings that fasten things together
    • Examples of ties include cables, rods, and chains.
  4. Adhesives:
    • Adhesives are used to bond two or more structural members together.
    • Examples of adhesives include thermosetting glues and solvent-based glues.
    • Thermosetting glues harden when they cool after being heated
    • Solvent-based glues harden and then dry out
  5. Melting:
    • Melting is used to connect two or more structural members
    • Examples of melting include welding and soldering.
    • Welding is melting pieces of material together whereas soldering is surrounding material with pieces