2.4 Introduction to frame structures

Technology

Grade 6

Structures

Introduction to frame structures

Assignment 1:

What is a frame structure?

[lo 2.2]

It consists of which are connected to construct a .

Support is often provided from the .

Thus the frame is sometimes hidden by a .

• A bridge or tower, such as a windmill, is a good example of a frame structure.

Assignment 2:

Let’s make paper straws to use for a frame structure. use old sheets of a4 paper, a thin dowel / long pencil and wood glue.

[lo 1.8]

Instructions:

a. Fold a sheet of paper to form a square. Cut off the remaining part.

b. Roll the paper around a pencil / dowel by starting at one corner of the square and ending at the opposite corner.

c. Roll the paper tightly around the pencil on a flat surface.

d. Apply paper glue to the end of the paper and stick it down firmly.

e. Remove the dowel from the straw by turning it slightly and pulling it out gently.

Assignment 3:

Let’s practise joining paper straws. there are different methods.

[lo 1.2, 1.8]

Method 1:

In order to obtain a longer straw, you can push the one end of the straw into the opening of the other while turning it. Use a little glue to join it properly.

Method 2:

Use a glue gun to glue the corners quickly and firmly.

Method 3:

a. Measure the required length of the straws. Cut them neatly and straight by using a pair of scissors.

b. Flatten the sides by pressing them down with a hammer or with your hand and then mark where the holes should be made.

c. Use the punch to make holes and connect the straws by using hole studs or rivets.

Method 4:

Use short pieces of bent pipe cleaners. Glue them firmly.

Background

Before you design and make your own bridge, we are going to examine different kinds of bridges.

What is a bridge?

It is a structure that spans a d istance and that can also support certain things.

• From the earliest times, man built bridges to link inaccessible areas in order to get somewhere. The GIRDER BRIDGE is the first and simplest type of bridge. The simplest example consists of one beam that rests on two areas on either side in order to link the two areas.

[LO 1.2]

Long ago people built girder bridges from stone, but they could only cover short distances. Today reinforced concrete beams, wood or steel are used to cover longer distances. Sometimes the beams are supported from below by one or more columns.

When a girder bridge is reinforced by means of a framework of rods in a triangular shape above or below the beam, such a bridge is called a TRUSSED BRIDGE. Bridges across railway lines are sometimes constructed in this way.

A Trussed bridge

AN ARCHED BRIDGE is built when deep ravines and rivers must be crossed and when it is impossible to erect shafts. The arch is built above or below the beam to enforce it and stretches from one bank to the other.

An Arched bridge

A SUSPENSION BRIDGE is built to span great distances. The road is literally suspended by very strong steel cables that are anchored to towers.

A Suspension bridge

Assessment

Learning Outcomes(LOs)

LO 1

TECHNOLOGICAL PROCESSES AND SKILLS

The learner will be able to apply technological processes and skills ethically and responsibly using appropriate information and communication technologies

Assessment Standards(ASs)

We know this when the learner:

1.2 finds out about existing products relevant to a problem, need or opportunity, and identifies and compares their design aspects (e.g. who it is for, what it is for, what it looks like, what it is made of, how well it works, whether it will affect the environment);

1.8 chooses and uses suitable tools to make products by measuring, marking out, cutting or separating, shaping or forming, joining or combining, and finishing the chosen materials;

LO 2

TECHNOLOGICAL KNOWLEDGE AND UNDERSTANDING

The learner will be able to understand and apply relevant technological knowledge ethically and

We know this when the learner:

2.2 demonstrates knowledge and understanding of the reasons for the deterioration of different materials, and ways of preserving them (e.g. drying, coating, canning, sealing).