MaterialsStructures-magazine

Contents What is a structure? . . . . . . . . . . . . . . . . . . . 2 How do human-made structures and natural structures compare? . . . . . . . . . . . . . . 44 How can we describe structures? . . . . . . . . . . . . 66 Which shapes and forms are used in structures? . . . . 88 Which shapes and forms are the strongest? . . . . . . 10 What makes up a structure’s frame? . . . . . . . . . . 112 What makes posts and beams strong? . . . . . . . . . 14 B

Note: The terms in red text can be found in the Glossary on page 32. What properties do materials have? . . . . . . . . . . 166 How is a structure’s purpose related to its material? . . 1188 How are building materials joined together? . . . . . . 2200 How can we evaluate structures? . . . . . . . . . . . 2222 Why do some structures fail? . . . . . . . . . . . . . 2244 How can we build a strong and stable structure? . . . . 2266 How can we test our structures? . . . . . . . . . . . . 2288 How can we modify our structures? . . . . . . . . . . 3300 Glossary . . . . . . . . . . . . . . . . . . . . . . . . 3322

What is a structure? Structures are all around us. Cabot Tower, Signal Hill, We might only think of buildings St. John’s and bridges when we think of structures.There are many more kinds, though.What makes something a structure? What materials are they made of? Confederation Bridge deck chair lobster traps 2

hand-made moccasins from Hopedale painted mailbox bat house root cellar, Elliston What do you know about structures and materials? What would you like to find out? 3

hHauonmwd ndaoant-umraaldsetruscttruurcetsures compare? spiderweb Humans are not the only ones who build structures. Animals build them, too.These are known as “natural” structures. How are natural structures similar to ours? How are they different? Can you find any structures that are similar? 4 entrance to train tunnel apartment building

entrance to burrow cocoon beehive fishing net Did You Know? sleeping bag Honeybees keep the eggs and larvae of their queen in the cells of their honeycomb. This is also where they store their honey. 5

How can we describe Different structures have different parts. If you know what the different parts are called, it is easier to talk about the structure. For example, not all bridges are built the same way.They have different parts for different purposes. beam bridge beam post beam arch bridge arch post 6

structures? beam suspension bridge post truss bridge truss beam St. Paul’s Cathedral in London, England dome Buildings serve a very different arch purpose from post bridges. Some of their parts may be the same while others are different. 7

Warheicuhssedhianpsetsruacndtufroersm?s Some shapes and forms are better for building structures than others. Which shapes and forms do you see in these structures? beaver lodge Sydney Opera House, Sydney, Australia 8

Eiffel Tower, Paris, France arches in front of St. John the Baptist Basilica, St. John’s downy woodpecker nest Norstead Viking Site, L’Anse aux Meadows 9

Warheicthhesshtarpoesnganedsfto?rms The weight that a When you push down But when you push down structure must support on the corner of a on the point of a triangle, is called its load. A square, the sides of the the base of the triangle load can be people, square push outward pushes the sides away cars, furniture, snow, and the sides collapse. from one another so and even the forces of they don’t collapse. wind and gravity. Shapes and forms can help a structure to better support its load. Some shapes and forms are stronger than others. A triangle is an example of a strong shape. An arch is an example of a strong form. Where have you seen these shapes and forms? 10

When you push 11 down on the top of an arch, it makes the sides of the arch bend outward. But when the arch is supported, the supports push the sides together and keep them from bending.

What makes up a structure’s The frame of a structure is like its skeleton. It holds the structure together and supports all the other parts. In a building, the frame includes the foundation, the posts (the vertical pieces that stand up), and the beams (the horizontal pieces that lie sideways).Together, these parts hold up the roof, walls, and floors. roof post wall 12

frame? foundation beam The foundation is the lowest part of a structure. It supports the load of the structure. Builders often make foundations for homes out of concrete or cement blocks. Why do you think these materials are used? floor 13

What makes and strong? Posts and beams are used in many types of structures. Look at each picture and think about how posts and beams are being used. How strong do they need to be? What can make them stronger? What materials are they made from? Fogo Island Inn stairs with railing fence at L’Anse aux Meadows 14

fishing stage lean-to shelter bridge posts 15

What properties do materials have? Have you ever seen a house birch tree made of rubber? A boat made birchbark canoe of stone? Or a car made of paper? Some materials are better than others for making certain structures. Every material has different properties, or characteristics, that make it good for building some things and not for building others. Look at each pair of pictures. Why do you think each material was used to make the related structure? Which properties does the material have that make it good for building such a structure? 16

Did You Know? traditional Inuit shelter Caribou hides are used to build traditional Inuit shelters. Why do you think caribou hides are a good material to use? granite granite lighthouse, Rose Blanche cut logs wooden house, St. John’s 17

How is a structure’s purpose related to its material? A structure has a purpose, or a reason for being built. It may provide shelter or transportation. It may help perform a specific task. When choosing materials for a structure it helps to think about its purpose. For example, if a structure is to provide shelter, it might be best to use a waterproof material. If a structure is to help dig a hole, it would not need to use a waterproof material. What is the purpose of a doghouse? How might knowing this purpose help with choosing the best materials? 18

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How are building materials joined together? Building materials are joined with fasteners. Some fasteners are fixed (do not move) and some need to move.The kind of fastener used depends on the purpose of the joint and on the kind of material being used. What kinds of joints and fasteners can you see in these pictures? 20

How would you use fasteners like these? rubber bands glue paper clips 21

evHalouwatecastnruwcetures? Mi’kmaq wigwam A structure must work well for its purpose, for its user, and for its environment. In what environment would each of these homes work? What purpose would it meet? Who might use it? house on stilts 22

igloo Norse house at L’Anse aux Meadows saltbox house 23

fail?Wsthruycdtousormese We know what makes structures strong and stable.We also know how important it is to choose the best materials for different structures. But structures can still fail, sometimes because of a mistake and sometimes because of a natural disaster. What mistakes were made when building the structures shown here? What could have been done to prevent these disasters? The Leaning Tower of Pisa in Italy was built of marble, a heavy kind of stone. But the ground it was built on was very soft, and the tower sank down on one side more than on the other. 2244

The Mon Bridge in Kanchanaburi, Thailand, is made of wood. In 2013, heavy flooding caused part of the bridge to collapse. In 2009, the 13-storey Lotus Riverside apartment building in China fell over when the posts in its foundation snapped. Workers had dug a hole for a garage on one side of the building, and piled all the soil on the other side. When it rained, the soil became wet and very heavy. That weight pushing against the building, combined with the hole on the other side, caused the building to fall over. This parking garage in California collapsed because of an earthquake in 1994. The shaking floors of the garage caused the middle columns to collapse. 2255

How can we build a strong and stable structure? Architects and support engineers are always posts trying to make their structures stronger and more stable. Here are three examples of structures with parts that are designed to do exactly that. right-side-up post This concrete upside-down post bridge has several support posts along the outside of the arch. This parking garage uses triangular posts. Some are upside down so that the weight from above is resting on two angled posts. Others are right-side up so that the weight is 26 resting on the point of one post.

Broadgate Tower in London, England, is a skyscraper that was built with a frame around it to help with stability. The frame is made of steel beams in triangle shapes. Did You Know? An architect designs structures. The architect must think about the purpose of the structure, the weather it will exist in, as well as the money and materials available to construct it. An engineer plans and builds structures that solve a problem. The engineer must think about the exact size and kinds of materials needed to make the structure purposeful and safe. 27

How can we test our You need to see how big a load a structure can support to test its strength. To test the stability of a structure, you need to see how much vibration it can take or how forceful a wind it can stand up against. Can you identify what is being tested in each picture? [reference images a bridge with only – all pictures several books will be illustrated in on top a matching style] 7” 6” 28

structures? [reference image to be illustrated] 4.5” 4.75” a tower structure on a shake table 4” a bridge structure with a bucket of water suspended from it 5” [diagram of popsicle-stick tower in front of an electric fan] [reference image 6.25” 5.5” to be illustrated] 4.5” 4.25” 29 a tower structure in front of a fan

How can we modify The toothbrush has come a long way in 5500 years! It has been modified, or changed, many times. Why do you think these changes were made? 3500 BCE 15th century 1780 1938 1954 THE CHEW THE BRISTLE THE ADDIS DR. WEST’S THE STICK BRUSH TOOTHBRUSH MIRACLE– BROXODENT Frayed wood Hog hair on Hog, cow, or TUFT ELECTRIC Egypt and bamboo or bone horse-tail hair TOOTHBRUSH TOOTHBRUSH Babylonia China on bone Nylon bristles on Plugs into a England plastic wall socket 30 United States Switzerland

our structures? This timeline presents changes in the development of the toothbrush. How else could this information have been presented? 1961 2007 2014 2017 THE GENERAL THE ULTIMA THE ISSA ELECTRIC THE KOLIBREE ELECTRIC ULTRASONIC TOOTHBRUSH ARA AUTOMATIC TOOTHBRUSH Antibacterial silicone Integrated artificial TOOTHBRUSH Uses soundwaves “bristles” intelligence (AI) Rechargeable with a United States Sweden France charging dock United States 31

arch: a curved structure; the separate parts of the curve push against each other and hold up the arch beam: a long horizontal piece of the building frame that lies sideways; it works with posts and other beams to support a structure dome: a circular structure in which the sides and top curve together; roofs may be shaped like domes fastener: a device that joins two or more objects together form: a 3-D figure such as a post, beam, frame, arch, or dome foundation: the base that supports the load of a building; works with the posts and beams to create a frame frame: the structure that holds a building together joint: a place where two or more pieces of a structure are joined together load: the weight that a structure, or part of a structure, must support post: the vertical part of a building frame that stands straight up; it works with beams and other posts to support a structure shape: a 2-D flat figure such as a square, rectangle, circle, or triangle structure: anything that is built, has more than one part, and serves a specific purpose truss: a framework consisting of triangular shapes for 32 supporting a roof or a bridge

Answers for back cover What is How do construction What did the the world’s workers party? worker say to tallest building? the wall? Answer One more crack like that and I’ll plaster ya! Answer Answer Why did the nosy roofer lose his job? The library because They raise it has the most the roof! Answer stories. What did one wall Because he What goes up and down say to the other wall? couldn’t stop but never moves? eavesdropping. Answer Answer I’ll meet you at the corner. Stairs. Grade 3: Unit 2: Materials and Structures Magazine Copyright © 2018 Scholastic Canada Ltd. 175 Hillmount Road, Markham, Ontario, Canada L6C 1Z7 Written by Kelly Stern Photos ©: cover: David Litschel/Alamy/All Canada Photos; inside cover top left: All Canada Photos/Fotolia; inside cover bottom left: vyenel/iStockphoto; inside cover bottom right: Cindy Hopkins/ Alamy/All Canada Photos; 1 top left: First Light/All Canada Photos; 1 top right: 4kodiak/iStockphoto; 1 bottom right: QQ7/iStockphoto; 2 -3 background: Island Images/Alamy/All Canada Photos; 2 top right: Terrance Klassen/Alamy Images; 2 bottom left: Michelle Gilders/Alamy/All Canada Photos; 2 bottom right: David Litschel/Alamy/All Canada Photos; 3 top left: Cindy Hopkins/Alamy Images; 3 top right: Norman Pogson/Alamy Images; 3 bottom left: Zoonar GmbH/Alamy/All Canada Photos; 3 bottom right: Terrance Klassen/Alamy/All Canada Photos; 4 top left: danmir12/Fotolia; 4 bottom left: zhaubasar/Fotolia; 4 bottom right: Lester Balajadia/Shutterstock; 5 top left: Lars Johansson/Fotolia; 5 centre left: Alan Bourne/Alamy/All Canada Photos; 5 bottom left: Aleš Nowák/Fotolia; 5 top right: All Canada Photos/Fotolia; 5 centre right: Vova Shevchuk/Shutterstock; 6 top right: Barrett & MacKay/All Canada Photos; 6 centre: ZernLiew/iStockphoto; 6 bottom left: ZernLiew/ iStockphoto; 6 bottom right: Arco Images GmbH/Alamy Images; 7 top left: Josef Hanus/Alamy Images; 7 top right: ZernLiew/iStockphoto; 7 centre left: ZernLiew/iStockphoto; 7 centre right: Radius Images/All Canada Photos; 7 bottom left: Justin Kase z05z/Alamy Images; 7 bottom right: nicoolay/iStockphoto; 8 top: beklaus/iStockphoto; 8 bottom: vyenel/iStockphoto; 9 top left: Demid/ iStockphoto; 9 bottom left: INTERFOTO/Alamy Images; 9 top right: S. Vincent/Alamy/All Canada Photos; 9 bottom right: William Leaman/Alamy/All Canada Photos; 10 top: Lester Balajadia/ Shutterstock; 11 top: First Light/All Canada Photos; 12-13 background: Christian Delbert/Fotolia; 12 bottom: Dave Reede/All Canada Photos; 13 top: Esa Hiltula/Alamy Images; 14 bottom left: Terrance Klassen/Alamy/All Canada Photos; 14-15 top centre: KarenMassier/iStockphoto; 14-15 bottom centre: GeorgeBurba/iStockphoto; 15 top right: Ron Watts/All Canada Photos; 15 centre right: SF photo/Shutterstock; 15 bottom right: Paul Broadbent/Alamy/All Canada Photos; 16 top: Ernie Janes/Alamy/All Canada Photos; 16 bottom: Hemis/Alamy/All Canada Photos; 17 top: Cindy Hopkins/Alamy/All Canada Photos; 17 centre left: Klaus Lang/All Canada Photos; 17 centre right: Mike Grandmaison/All Canada Photos; 17 bottom left: rootstocks/iStockphoto; 17 bottom right: Robert Chiasson/All Canada Photos; 20 top: Doug Norman/Alamy Images; 20 bottom: UrbanImages/Alamy Images; 21 top left: SimplyCreativePhotography/iStockphoto; 21 bottom left: Ernesto Sander/Alamy Images; 21 top right: Skyhobo/iStockphoto; 21 rubber bands: Digifoto Ruby/Alamy Images; 21 glue: Judith Collins/Alamy Images; 21 paper clips: Helen Sessions/Alamy Images; 22 top right: S. Forster/Alamy/All Canada Photos; 22 bottom: David Wei/Alamy Images; 23 top left: ArcticPhoto/All Canada Photos; 23 top right: imageBROKER/Alamy Images; 23 bottom: Terrance Klassen/ Alamy/All Canada Photos; 24: QQ7/iStockphoto; 25 top: Veeravong Komalamena/Alamy/All Canada Photos; 25 centre: Bloomberg/Getty Images; 25 bottom: Spencer Grant/Getty Images; 26-27 background: 4kodiak/iStockphoto; 26 bottom left: VIEW Pictures Ltd/Alamy/All Canada Photos; 27 right: Graham Prentice/Alamy/All Canada Photos; 32 arch: S. Vincent/Alamy/All Canada Photos; 32 beam: Arco Images GmbH/Alamy Images; 32 dome: Justin Kase z05z/Alamy Images; 32 fastener: Ernesto Sander/Alamy Images; 32 form: Mike Grandmaison/All Canada Photos; 32 foundation: Esa Hiltula/Alamy Images; 32 frame: Christian Delbert/Fotolia; 32 joint: Skyhobo/iStockphoto; 32 load: David Wei/Alamy Images; 32 post: David Wei/Alamy Images; 32 shape: INTERFOTO/Alamy Images; 32 structure: David Litschel/Alamy/All Canada Photos; 32 truss: Radius Images/All Canada Photos. Illustrations ©: 18-19: Dean Griffiths; 28-29: Ted Hammond; 30-31: Brad Forsyth; back cover: David Sones ISBN 978-1-4430-4767-8 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, in any form or by any means, without the prior written consent of the publisher or a license from The Canadian Copyright Licensing Agency (Access Copyright). For an Access Copyright license, call toll free to 1-800-893-5777. Printed in Canada

Joke Under Construction What is How do the world’s construction tallest building? workers party? What did the What did one worker say to wall say to the the wall? other wall? What goes up Why did and down but the nosy never moves? roofer lose his These buISBN 978-1-4430-4767-8 ildingMaterials and Structures job? jokesMagazine Bcode have nailed it! Look for answers. inside 9 781443 047678 Materials and Structures