# Shapes And Structures

Triangular shapes and structures are very powerful geometric forms, which makes them essential when constructing strong and sturdy buildings of any kind. Some shapes are wider at the bottom than the top. This is called tapering. A tapering shape on its side is a wedge. It can be used to force even giant blocks apart.

When engineers design structures, they want to be certain that the structure will be able to withstand the weight of the structure. That is, they do not want the structure to collapse as a result of the application of a force on the structure. For example, bridges must be able to support the weight of the materials used to construct the bridge as well as the weight of all of the vehicles passing over it.

The triangle is one of the forms that can withstand a great deal of weight. The triangle is one of the most popular shapes among architects. The triangle is the most powerful form because it is capable of maintaining its shape, has a solid foundation, and can provide enormous support. But what is it about triangles that makes them so excellent at this?

Now, let’s take a look at how a triangle transmits kinetic energy.

When a force or load, is applied to one of the triangle’s corners, the force is dispersed along each side of the triangle. There is a tight squeeze between the two sides of the triangle. Compression is another term for this kind of squeezing. The third side of the triangle is dragged, or stretched, in the direction of the other two sides. Tension is another term for this kind of straining.

There are three kinds of triangles: the equilateral triangle, which has three equal-length sides, the isosceles triangle, which has two equal sides, and the scalene triangle, which has no sides of equal length. The equilateral triangle is the most common. Aside from their many variations, triangles have certain characteristics in common, such as the fact that they all have three sides and are very sturdy.

The triangle’s resistance to pressure may be shown by examining how different forms fare under pressure. It is possible to force a square to move from one side to another, ultimately creating a rhombus shape. The pressure given to a triangle will not break the triangle’s structure; rather, it will absorb the pressure and stay rigid. A  polygon (example rectangle, pentagon, hexagon etc) is a shape formed by connecting straight lines, and the triangle is the only polygon that will not move when subjected to force.

Triangles are used to support some of the world’s most renowned architectural wonders, like the Eiffel Tower, the Great Pyramids of Giza, and the Louvre Pyramid, to create magnificent and long-lasting buildings. The 30⁰-60⁰-90⁰ triangle and the 45⁰-45⁰-90⁰ triangle are two of the most often seen triangles in architecture.

# The great pyramids

A pyramid is a shape that has triangular sides meeting in a point. The great pyramids of Giza in Egypt are tombs for kings (pharaohs) that were built by the Ancient Egyptians over 3000 years ago.

The builders of the pyramids found out about strong shapes by trial and error. At first they built a pyramid with steeply sloping sides. They found that this kept falling down.

Having learned this lesson they built pyramids with less steep sides.

# Triangular Shape

Wedges and pyramids are examples of a triangular shape that can stand up to great forces. It has been used in the design of the skyscraper shown in the picture above.

## Make a door stop | Triangular Shape

A wedge is a tapering shape that makes a good kind of doorstop. Ask a grown-up to saw a piece of wood to give several wedge shapes like the ones shown below.

Try each wedge in turn to see which one is best at holding a door open. When you have found the one that works best, compare it with a doorstop that can be bought in a shop. Are the shapes similar?

## Opening wedges | Shapes and Structures

Wedges are good at prising things apart because they have a thin blade at one end which changes to a thick blade at the other. You can see a wedge-shape at the end of this chisel. It is used for making a cut in wood.

## How Triangles Are Employed in Bridge Construction

Triangles are often utilized in the construction of bridges. Bridges are used to join together several triangles. They use compression and tension in various areas of the body.

Trusses may be constructed by combining triangles. Trusses are employed in a wide range of constructions, including roofs, bridges, and buildings, among others. Trusses are made up of horizontal beams and diagonal beams that are combined to create triangles. Truss bridges are bridges that are constructed using trusses.

There are many distinct kinds of trusses that may be utilized in the construction of bridges. The arrangement of the horizontal and diagonal beams determines the kind of truss that is used. There are four major types of trusses that are utilized in the construction of bridges.

## Warren Truss

This is accomplished via the use of diagonal beams that create equilateral triangles. These triangles have three sides that are the same length as one another.

## Howe Truss

This bridge is constructed with diagonal beams that slope upwards toward the center of the bridge until they meet in an upright isosceles triangle.  This kind of triangle has two sides that are the same length and a third side that has a different length from the other two sides.

## Pratt Truss

Using diagonal beams that slope downhill towards the center of a bridge until they meet in an upside down isosceles triangle, this structure is constructed.

## K Truss

This is a more complicated kind of truss that is constructed from back-to-back triangles that are arranged in the shape of a K shape.

## How Triangles Are Employed in Roof Construction | King Post Truss

A King Post truss is a kind of truss that is frequently used to support roofs and is referred to as such. A king post truss is made up of two beams: a horizontal beam known as the tie beam and a vertical beam known as the king post (hence its name). There are two posts that connect the top of the king post with the tie beam, forming triangular forms at the top of the structure.

Principal rafters are the pillars that support the roof of the building. Within these triangles, diagonal struts are placed to link the main rafters to the king post, which is supported by the king post itself. The addition of these struts strengthens the roof even further.

(1) King post

(2) Tie beam

(3) Principal rafters

(4) Struts

These king post trusses are then linked together with additional beams to create a strong and sturdy framework that is capable of supporting a roof structure.

(1) The ridge beam,

(2) the purlins, and

(3) the common rafters

This is an example of a “double roof,” which is comprised of main rafters and common rafters on the same roof.

When it comes to engineering, triangles are very essential shapes to understand. In all kinds of constructions — from bridges to homes and even aircraft — the usage of triangular shapes will continue to be essential!