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Structures. What do we understand when we talk about structures in Design and technology?. Lesson Objectives: To understand the forces and the parts that form structures. Plan of Lesson: Setting the learning objectives 2 mins
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Structures What do we understand when we talk about structures in Design and technology?
Lesson Objectives: To understand the forces and the parts that form structures. Plan of Lesson: Setting the learning objectives 2 mins Starter Task – exploring different ways of making paper stronger 5 mins What are structures and what parts and forces are there 8 mins Existing structures from various cultures 5 mins Introduction to task and brief 5 mins Making your own towers 20 mins Testing the weight of your towers 10 mins Evaluation-What worked, what didn’t work, how could they be made better- information on struts and ties 5 mins
What is a structure?Definition • A Structure is an object or a collection of objects put together in a particular wayto withstand load.
Examples of man-made structures Roof Trusses Buildings Bridges Play equipment i.e climbing frames, slides Brackets Tables Scaffolding Chairs
Examples of structures in nature • Snails shell • Trees • Coral • Cob-webs • Skeleton • Beaver Dams
Starter task- Making paper stronger • How can you make your piece of paper stronger? • Think of different shapes that you can use and different ways of folding paper
FRAMES Many structures are based on a frame. We use frames every day ,for example, a stool is a frame on which we sit. Buildings are based on frames and this is why they can be built very high. Everywhere we look in towns and cities we see examples of structures based on frames. Can you name any famous structures, anywhere in the world, that are based on a frame ? The square frame is strong when pressure is straight down on it. If pressure is from the side it tends to be weak and it can collapse. A triangular frame is very strong. Many structures and buildings are often made up of this type of shape.
Forces Shear Force This is when two forces are going in two different directions. The arms of the scissors move in different directions from the pin. • Tension • Tension is when something is being pulled or stretched Torsion Torsion is when something is being twisted. Compression This is when something is squashed like if you stand on a coke can, your leg is compressing the can.
Struts and Ties All structures have forces acting on them. The part of the structure that has a tension acting on it is called a TIE and the part that has compression acting on it is called a STRUT. Wall The beam is held in position by a steel rod. The weight of the beam is stretching (pulling) the rod. Which type of force is this? Roof The roof beams are being pushed down from the weight of the tiles on the roof. What is the force that pushes? Flagpole The wires on either side of the flagpole are being stretched. Why is the polebeing compressed?
Examples of structures The Egyptian Pyramid • Built around 2600 B.C. • From over 2 million blocks of stone • They have a square base and triangular sides • Tombs for pharaohs
Examples of structures The Eiffel Tower (France) • Built between 1887- 1889 • 9441 tons of wrought iron • 324 meters tall • 18038 pieces of wrought iron were joined together to create the Eiffel Tower • During strong winds, the Eiffel Tower sways up to 15 c.ms at its top
Examples of structures The Spinnaker Tower (England) • It was opened in 2005 • 1200 tons of steel was used to construct the Spinnaker • The spire is 27m tall • The Tower’s ‘legs’ are constructed from concrete • The total weight of the Tower is heavier than 30,000 tons • 115m up and in high winds, the Tower can move approximately 15 c.ms
Teams Team 1 – Lance & Biff Team 2 – Annie’s Team 3 – Chris & Peter Team 4 – Josie & Ben
Brighton i360 Designed by Marks Barfield also responsible for the the London Eye. Will (hopefully) boost tourism in Brighton especially during the Olympics. Visitors will be able to enjoy 360 degree panoramic views of Brighton and on a clear day can see up to 25 miles along the South coast. Intended to be: A unique experience A gentle landmark A visitor destination A catalyst for long-term regeneration
Brighton needs YOU! The original plans for the Brighton i360 observation tower have been scrapped due to lack of funding and fears it will attract extra terrestrials. Brighton council have turned to YOU and your team mate to build a new (cheaper) observation tower for the sea front from the range of materials provided. They are pretty relaxed about the design of the new tower and the methods you use to build it. HOWEVER! The tower must meet the following conditions; It must be at least 300mm height (it can be as wide as you wish) It must holda minimum weight of 100g It must have an observation pod on top (use the cup provided) You may only use materials provided ( and cannot swap or steal from other groups) It must NOT fall down when the minimum weight is added. If the tower doesn’t meet these specifications, Brighton will not have a new tower and your team will FAIL
Planning and Design Think about the different ways you can design the tower, draw your design ideas below and select the one you think will be most successful.
De-brief • What worked well? • What challenges did you encounter and how did you overcome them? • Did you build the tallest tower you could? Why or why not? • How similar is your design to others in the room?