Bridges.Level C Bridges Bridges help us get across places. Some bridges go over water. Some go over land. The part of the bridge that you can walk or drive on is called the deck. Bridges must be very strong and sturdy sturdy neurological disease in sheep caused by the pressure of a Taenia multiceps metacestode. Called also gid. . A bridge not only has to support its own weight, but it must support the heavy traffic that crosses it. Most large bridges today are made of heavy materials, like concrete and steel. A bridge must also be able to stand up to all sorts of wind and weather. Piers This article contains a list of piers throughout the world. Australia
Some bridges are very simple, like a log that falls across a creek. Other designs are far more complicated. * A beam bridge is like a log bridge, but it is supported at both ends. Many highway overpass bridges are made with this design. * An arch bridge is stronger than a beam bridge. Its curved shape pushes the weight of the bridge sideways into its supports. * A truss truss, in architecture and engineering, a supporting structure or framework composed of beams, girders, or rods commonly of steel or wood lying in a single plane. bridge uses triangle supports that make it very strong, so it needs less piers. * The longest bridges Longest bridge may refer to:
DID YOU KNOW?? New York's Verrazano Narrows Noun 1. Verrazano Narrows - a narrow channel of water separating Staten Island and Brooklyn Greater New York, New York, New York City - the largest city in New York State and in the United States; located in southeastern New York at the mouth of the Hudson river; a Bridge has the longest main span in the U.S. It is 60 feet longer than San Francisco's Golden Gate Bridge Golden Gate Bridge, across the Golden Gate from San Francisco to Marin Co., W Calif.; built 1933–37. Its overall length is 9,266 ft (2,824 m); its main span across the strait, 4,200 ft (1,280 m), is one of the longest bridges in the world. Joseph B. . DID YOU KNOW?? Some bridges are built on a row of floating boats. These are called pontoons. Vocabulary Carefully follow the arrow clues and fill in these missing letters. [ILLUSTRATION OMITTED] Weekly Lab Let's test which shapes make the strongest piers. You need: large index cards, tape, books Step 1: Make 2 of each of these shapes. Step 2: Place some books on top of each pair. Which pier shapes were the strongest? Step 3: Design and test some piers of your own. Use lightweight books! Weekly Problem Trusses give bridges strong support. They can be made of wood or metal. Use the chart to help you color in Verb 1. color in - add color to; "The child colored the drawings"; "Fall colored the trees"; "colorize black and white film" color, colorise, colorize, colour in, colourise, colourize, colour the different triangle shapes found in these truss bridges. * red ** blue *** green **** purple DID YOU KNOW?? While covered bridges can keep travelers dry in the rain and snow, the covers were actually built to protect wooden trusses from rotting. DID YOU KNOW?? "Galloping gal·lop·ing adj. 1. Of or resembling a gallop, especially in rhythm or rapidity. 2. Developing or progressing at an accelerated rate: galloping technology. 3. Gertie" was the name of a suspension bridge that was too light. Wind caused it to sway, twist, and finally collapse. Writing for Science BRIDGES BUILDERS WANTED!!! Write a letter for this Want-Ad. Tell them why you are the right person for the job! DID YOU KNOW?? It takes 3 years of painting to cover the mile-long Forth Rail Bridge in Scotland from end to end. This keeps it from rusting rusting: see corrosion. . DID YOU KNOW?? Standing on the arched center of the New River Gorge Bridge Noun 1. New River Gorge Bridge - a steel arch bridge across New River at Fayetteville, West Virginia Fayetteville - a town in central West Virginia on the New River is like standing on top of a 60 story building. Challenge How strong is your bridge deck? You need: 2 stacks of books about 10 cm tall (4 in.), pennies, construction paper (8 1/2 x 11 in.), ruler * Place your 2 stacks of books about 10 cm (4 in.) apart. * Next, lay your piece of paper flat across both stacks. * Carefully put pennies on the middle of the paper, one at a time. * Now, make a paper arch. Bend your paper into a curve and put it between the books. Place pennies on top of your arch. Which shape is stronger? How many pennies did each hold? DID YOU KNOW?? Compteted in 1998, the Akashi Kaikyo Bridge in Japan is currently the world's longest suspension bridge, measuring 12,828 feet. It would take 4 Brooklyn Bridges Brooklyn Bridge, vehicular suspension bridge, New York City, southernmost of the bridges across the East River, between lower Manhattan and Brooklyn; built 1869–83. The achievement of J. A. Roebling and his son W. A. Roebling, it has a span of 1,595. to equal that distance! DID YOU KNOW?? Boston's Charles River Charles River River, eastern Massachusetts, U.S. The longest river wholly in the state, it flows into Boston Bay after a course of about 80 mi (130 km). Navigable for about 7 mi (11 km), its estuary separates the cities of Boston and Cambridge. Bridge, completed in 2001, is wide enough to carry 10 lanes of traffic! Puzzel Write in the letter to match each bridge type with its picture. 1) simple arch bridge [ILLUSTRATION OMITTED] 2) truss bridge [ILLUSTRATION OMITTED] 3) suspension bridge [ILLUSTRATION OMITTED] 4) arch and truss bridge [ILLUSTRATION OMITTED] 5) suspension bridge with trusses [ILLUSTRATION OMITTED] DID YOU KNOW?? When it was built in 1883, the Stone towers of the Brooklyn Bridge were the tallest structures in all of New York City New York City: see New York, city. New York City City (pop., 2000: 8,008,278), southeastern New York, at the mouth of the Hudson River. The largest city in the U.S. . Bridges Background Bridges are a technological marvel. Their development has aided travel, led to the growth of communities, and has helped to establish continuing trade routes. The rapid expansion of railways during the last century challenged engineers to overcome many obstacles. Foremost among these was how to support the tremendous weight of railroad railroad or railway, form of transportation most commonly consisting of steel rails, called tracks, on which freight cars, passenger cars, and other rolling stock are drawn by one locomotive or more. cars, so they could travel easily across hilly hill·y adj. hill·i·er, hill·i·est 1. Having many hills. 2. Similar to a hill; steep. hill and rugged terrain. The B & O Railroad even established an engineering school to solve these types of problems. Engineers must decide on the best design and the best materials to use for each bridge they build. For centuries, bridges have been constructed with materials like rope, stone, wood, and iron. The Romans were master bridge builders Bridge Builder is a series of computer games developed and published by Chronic Logic. Bridge Builder is the first in the series, followed by Pontifex, Pontifex 2 (later renamed to Bridge Construction Set[1]), and Bridge It. and invented concrete. They used this strong building material to construct hundreds of bridges, many of which are still standing today. Steel is now used for most modern bridges. Even concrete bridges use steel rods for reinforcement reinforcement /re·in·force·ment/ (-in-fors´ment) in behavioral science, the presentation of a stimulus following a response that increases the frequency of subsequent responses, whether positive to desirable events, or . Types of Bridges There are many types of bridges. Some are very simple, like a log that has fallen across a creek. Others are far more complex. Some are the result of a combination of designs that work together to provide added strength. Most bridges rely on piers for support. Bridges are designed to be strong and sturdy, and to withstand all sorts of weather conditions. * Beam Bridges--A simple beam bridge is similar in design to a log across a stream, except that the deck (the part of the bridge you can walk or drive on) is supported at both ends. Many highway overpass bridges are made using this design. * Arch Bridges--Rather than having its weight pushed straight down into its supports like a beam bridge, an arch bridge pushes its weight down and out towards its strong side supports. Both arch and beam bridges are designed to handle the forces of compression caused by the weight of traffic traveling over them. The arch shape results in a stronger bridge design than the beam. * Truss Bridges--Rigid triangular-shaped trusses add strength to all types of bridges. These different criss-cross truss designs were often named after the engineers who first patented them. * Suspension Bridges--The longest bridges are suspension bridges. The decks of these bridges are suspended sus·pend v. sus·pend·ed, sus·pend·ing, sus·pends v.tr. 1. To bar for a period from a privilege, office, or position, usually as a punishment: suspend a student from school. by strong cables hung from high towers and anchored at both ends. The cables of a suspension bridge are under constant tension, much like a fully stretched rubber band. They are very thick (the cables on the Golden Gate Bridge are 92.5 cm [36.5 in.] in diameter) and weigh thousands of pounds per foot. Suspension bridges are designed to sway in the wind. * Cantilever Bridges--A cantilever bridge extends out beyond its supporting piers and usually has a span suspended between two outstretched out·stretch tr.v. out·stretched, out·stretch·ing, out·stretch·es To stretch out; extend. outstretched Adjective "arms." These bridges are constructed "up and out" from opposite supporting sides. * Movable Bridges--To allow for tall boat traffic to pass through, many bridges must open up or have sections that move apart. The bascule bascule /bas·cule/ (bas´kul) [Fr.] a device working on the principle of the seesaw, so that when one end is raised the other is lowered. or see-saw bridge is a hinged bridge with counterweights that draw the bridge open, much like the drawbridges of medieval castles. Some movable bridges have spans that swing out on a swivel base or move up and down on pulleys like an elevator elevator, in machinery elevator, in machinery, device for transporting people or goods from one level to another. The term is applied to the enclosed structures as well as the open platforms used to provide vertical transportation in buildings, large ships, . * Covered Bridges--The roofs and covers on these bridges help prevent heavy snow and bad weather from stopping bridge traffic. People once thought that livestock livestock Farm animals, with the exception of poultry. In Western countries the category encompasses primarily cattle, sheep, pigs, goats, horses, donkeys, and mules; other animals (e.g., buffalo, oxen, or camels) may predominate in other areas. were less afraid to cross these bridges than uncovered Uncovered may refer to:
Many bridges combine several elements of different designs to create the strongest and most durable bridge for the area needed (and with the materials available). In some remote areas, footbridges have been constructed out of wooden planks interlaced Refers to a display system or image that uses interlacing and does not render contiguous lines one after the other. See interlace and interlaced GIF. with twine twine: see cordage. or vines. In other places, bridges are constructed across floating boats to create pontoon pontoon, one of a number of floats used chiefly to support a bridge, to raise a sunken ship, or to float a hydroplane or a floating dock. Pontoons have been built of wood, of hides stretched over wicker frames, of copper or tin sheet metal sheathed over wooden bridges. Once basic engineering principles have been met, bridge designers are limited only by their imaginations and creativity. Building a Bridge When planning a bridge, engineers must consider location, design, cost of materials, height needed for river traffic, and whether the bedrock will be strong enough to support a foundation. If a pier is to be built underwater Underwater 1. The condition a call option is in when its strike price is higher than the market price of the underlying stock. 2. The condition a put option is in when its strike price is lower than the market price of the underlying stock. , a cofferdam is first constructed out of pilings. Then the water is pumped out and concrete poured in. If there is a lot of sand or mud, a "bottomless bot·tom·less adj. 1. Having no bottom. 2. Too deep to be measured: a bottomless glacier lake. 3. " caisson caisson (kā`sən, –sŏn) [Fr.,=big box], in engineering, a chamber, usually of steel but sometimes of wood or reinforced concrete, used in the construction of foundations or piers in or near a body of water. There are several types. is sunk, until solid bedrock is located. Caissons can go deeper than cofferdams and are filled with compressed air compressed air, air whose volume has been decreased by the application of pressure. Air is compressed by various devices, including the simple hand pump and the reciprocating, rotary, centrifugal, and axial-flow compressors. to keep water out and workers alive. Scaffolding is sometimes used to help hold up a bridge while under construction. Cranes or helicopters are often used to hoist hoist: see winch. pre-built decks into place. For most suspension bridges, towers are constructed first. Because each foot of cable weighs thousands of pounds, the cables are usually spun from the top of these towers, rather than assembled as·sem·ble v. as·sem·bled, as·sem·bling, as·sem·bles v.tr. 1. To bring or call together into a group or whole: assembled the jury. 2. on the ground and raised up. For bridges that cross deep gorges Gorges, the plural of the French word for "throat", usually refers to a canyon. Gorges is the name or part of the name of several communes in France:
Not only have bridges led to ease of travel and the connection of different segments of our population, they have become a key part of our urban landscape. From the serene strength of the Golden Gate Bridge spanning across the San Francisco Bay San Francisco Bay, 50 mi (80 km) long and from 3 to 13 mi (4.8–21 km) wide, W Calif.; entered through the Golden Gate, a strait between two peninsulas. , to the intricacy in·tri·ca·cy n. pl. in·tri·ca·cies 1. The condition or quality of being intricate; complexity. 2. Something intricate: the intricacies of a census form. Noun 1. of New York's skyline, bridges show us the beauty of human ingenuity. National Science Education Standards The National Science Education Standards (NSES) are a set of guidelines for the science education in primary and secondary schools in the United States, as established by the National Research Council in 1996. Unifying Concepts and Processes (K-8) * Systems, order, and organization * Evidence, models, and explanation * Constancy con·stan·cy n. 1. Steadfastness, as in purpose or affection; faithfulness. 2. The condition or quality of being constant; changelessness. Noun 1. , change, and measurement * Form and function Standard A: Science as Inquiry (K-8) * Abilities necessary to do scientific inquiry * Understanding about scientific inquiry Standard B: Physical Science (K-4) * Properties of objects and materials * Position and motion of objects (5-8) * Properties of changes of properties in matter * Motions and forces * Transfer of energy Standard D: Earth and Space Science (K-4) * Properties of earth materials Earth materials is a general term that includes rocks and materials that are not by definition rocks but are commonly regarded as rocks. Examples of the latter are coal and volcanic glass, which are not composed of minerals. (5-8) * Structure of the earth system Standard E: Science and Technology (K-4) * Abilities of technological design * Understanding about science and technology * Abilities to distinguish between natural objects and objects made by man (5-8) * Abilities of technological design * Understandings about science and technology Standard F: Science in Personal and Social Perspectives (K-4) * Types of resources * Changes in environments * Science and technology in local challenges (5-8) * Populations, resources, and environments * Natural hazards * Risks and benefits * Science and technology in society Standard G: History and Nature of Science (K-4) * Science as a human endeavor (5-8) * Science as a human endeavor * Nature of science * History of science Level Pre-A Main Concepts: Bridges make it easier for us to get across places that are hard to cross. Piers help give bridges support. Picture Activity Have your students look at the different bridges on the front page. Ask them what kinds of places bridges help us get across. Explain that bridges must be strong and sturdy. They must be able to carry heavy traffic and stand up to all kinds of wind and weather. Vocabulary First, go over the words in the small boxes together. Then have your students listen carefully. Tell them to draw a plane in the box over the bridge, a boat under the bridge, and a car on the bridge. Weekly Lab You need: large index cards, toilet paper rolls (or rolled and taped Index cards), lightweight books. Introduce the word piers to your students. Explain that piers help hold a bridge up and make it strong. Have them look back on the front page and point to the piers. Then ask if they think these index card "piers" can hold up (or support) a book. Have them first guess which of these shapes they think will be the strongest. Show them how to make the "V-shape" by folding their index cards in half. Then let them experiment using the folded shapes and rolled columns to support lightweight books (e.g., placing the cards in the same direction, facing each other, close together, far apart, etc.). Ask which shapes held the most books. (The V-fold is usually less stable than the column. It is most stable when the folded edges are facing each other.) Weekly Problem Answers: 3 green, 2 red. Have them first color the triangles on the left of the page. The ones that are pointing upward should be green, and the ones facing downward should be red. Explain that a truss bridge uses triangle shapes, because they make the bridge very strong--strong enough to carry trains. Next, have them look carefully at the bridge and color in all the bridge's upright upright said of limb joints and bones, especially in the horse. Indicates a lack of angulation in the joint, e.g. upright hock, or slope in a bone, e.g. upright pastern. In horses, often associated with a bumpy ride and a tendency to joint injury and lameness. triangles green, and all its downward triangles red. After coloring, have them count both directions of triangles and fill in the boxes. Storytelling Storytelling Aesop semi-legendary fabulist of ancient Greece. [Gk. Lit.: Harvey, 10] Münchäusen Baron traveler grossly embellishes his experiences. [Ger. Lit. Explain that some boats are too tall to fit under some bridges. Drawbridges can open up and let boats pass through. Many castles used drawbridges to help keep their enemies out. Some bridges that let boats pass through use elevators to lift up sections or have parts that swing out sideways. Challenge Answers: (Left to right) b, a, c. Though it fell down, London Bridge London Bridge, granite, five-arched bridge formerly over the Thames, in London, England. It is 928 ft (283 m) long and was designed by John Rennie and built between 1824 and 1831. actually lasted for 600 years. First built in 1176, it eventually had 19 different-sized archways stretching across the Thames River. Boats regularly hit its many piers in the fast currents of the water. Houses were built directly on the bridge, which added great pressure to its foundations. A whole row of unstable unstable, adj 1. not firm or fixed in one place; likely to move. 2. capable of undergoing spontaneous change. A nuclide in an unstable state is called radioactive. An atom in an unstable state is called excited. houses once fell into the river. A replacement bridge was built in 1831, and was moved to Arizona in 1972. Home Base This activity can be done at home or in class using a wide variety of around-the-house materials (e.g., assorted boxes, cans, paper towel or toilet paper rolls, magazines, books, blocks, etc.). Level A Main Concepts: Bridges make it easier for us to get across places that are hard to cross. Pier help give bridges support. Picture Activity Have your students look at the different bridges on the front page. Ask them what kinds of places bridges help us get across. Explain that bridges must be strong and sturdy. They must be able to carry heavy traffic and stand up to all kinds of wind and weather. Vocabulary First, go over the words in the boxes together. Then have them listen carefully. Tell them to draw a plane in the box over the bridge, a boat under the bridge, and a car on the bridge. Finally, have them circle the correct word in each box. Weekly Lab You need: large index cards, toilet paper rolls (or rolled and taped index cards), lightweight books. Introduce the word piers to your students. Explain that piers help hold a bridge up and make it strong. Have them look back on the front page and point to the piers. Then ask if they think these index card "piers" can hold up (or support) a book. Have them first guess which of these shapes they think will be the strongest. Show them how to make the "V-shape" by folding their index cards in half. Then let them experiment using the folded shapes and rolled columns to support lightweight books (e.g., placing the cards in the same direction, facing each other, close together, far apart, etc.). Ask which shapes held the most books. (The V-fold is usually less stable than the column. It is most stable when the folded edges are facing each other.) In addition, have them experiment by folding other shapes like triangles or boxes. Weekly Problem Answers: 4 green, 3 red. Have them first color the triangles on the left of the page. The ones that are pointing upward should be green, and the ones facing downward should be red. Explain that a truss bridge uses triangle shapes, because they make the bridge very strong--strong enough to carry trains. Next, have them look carefully at the bridge and color in all the bridge's upright triangles green, and all its downward triangles red. After coloring, have them count both directions of triangles and fill in the boxes. Writing for Science Since some boats are too tall to fit under bridges, drawbridges can open up and let boats pass through. Many castles used drawbridges to help keep their enemies out. Some bridges that let boats pass through use elevators to lift up sections or have parts that swing out sideways. Encourage your students to write longer stories on a separate sheet of paper. Challenge Answers: (Left to right) b, c, a, d. See TN Level Pre-A CHALLENGE for more information on London Bridge. Home Base This activity can be done at home or in class using a wide variety of around-the-house materials (e.g., assorted boxes, cans, paper towel or toilet paper rolls, magazines, books, blocks, etc.). Level B Main Concepts: Bridges must be strong and sturdy to carry heavy traffic. Piers help give bridges support. Vocabulary Answer: LONDON. ACROSS: 1) arch 6) suspension 8) over 9) deck DOWN: 2) cables 3) designs 4) truss 5) bridges 7) piers. Have your students refer back to the front page, if needed. Though it fell down, London Bridge actually lasted for 600 years. First built in 1176, it eventually had 19 different-sized archways stretching across the Thames River. Boats regularly hit its many piers in the fast currents of the water. Houses were built directly on the bridge, which added great pressure to its foundations. A whole row of unstable houses once fell into the river. A replacement bridge was built in 1831, and was moved to Arizona in 1972. Weekly Lab Your students' book stacks should be flat and equal in height. Have them place the pennies midway Midway, island group (2 sq mi/5.2 sq km), central Pacific, c.1,150 mi (1,850 km) NW of Honolulu, comprising Sand and Eastern islands with the surrounding atoll. Discovered by Americans in 1859, Midway was annexed in 1867. A cable station was opened in 1903. between the books. Pennies should be added until the paper sags or the pennies fall. Make sure that the bottom edges of the paper arch flare outward and are not curled curl v. curled, curl·ing, curls v.tr. 1. To twist (the hair, for example) into ringlets or coils. 2. under. If they are curled inward in·ward adj. 1. Located inside; inner. 2. Directed or moving toward the interior: an inward flow. 3. , their arch will collapse quickly. The arch is a stronger shape than the flat beam, because it better distributes the weight of the pennies--down the sides of the arch. The arch will usually hold about twice as many pennies. Weekly Problem Answers: Left to right: Blue, Green, Purple, Green, Purple, Green, Purple, Red, Blue, Red, Blue, Red, Blue, Green. Have them color in the color key (1) Also called "chroma key," it is a technique for superimposing one video image onto another. Widely used to place an interesting scene behind people such as a news reporter on TV, it is also used for creating special effects such as floating a car on the ocean. first. Point out that all the triangles in the key face different directions. Triangular shapes make a truss design bridge very strong and sturdy. This bridge is an example of a Burr Truss The Burr Arch Truss or simply Burr Truss or Burr Arch is a combination of an arch and a multiple kingpost truss design, invented in 1804 by Theodore Burr[1], patented on April 3, 1817[2], and used in bridges, usually covered bridges. . Writing for Science Bridge builders must work at great heights, sometimes as tall as a 100-story building. There are so few people who are able to spin the cables at the tops of suspension towers In an electric power transmission line, a suspension tower is where the conductors are simply suspended from the tower, the mechanical tension being the same on each side. , that skilled teams fly around the world from one job to another. Painters and maintenance workers also face the same dangers. Ask your students to imagine being 1000 feet in the air with the wind gusting and blowing, while trying to remove a rusty rust·y adj. rust·i·er, rust·i·est 1. Covered with rust; corroded. 2. Consisting of or produced by rust. 3. Of a yellowish-red or brownish-red color. 4. bolt bolt Mechanical fastener, usually used with a nut, for connecting two or more parts. Bolted joints can be readily disassembled and reassembled; hence bolts or screw fasteners are used more than other types of mechanical fastener. or paint a bridge. Have them think about the qualities a person would need to do this job. Challenge Answers: 1) b 2) c 3) a 4) d. Tell them to choose the name that best fits. Have them look back on the front page, if needed. Home Base This activity can be done at home or in class. Explain that piers help hold up a bridge and make it strong. Have them look back on the front page and find the piers. Then ask if they think these index card "piers" can support some lightweight books. (Have them try placing the cards in different directions, close together, far apart, etc.). Let them experiment to see how many books each shape can hold and which shape worked the best. (The V-fold is usually less stable than the columns. It is most stable when the folded edges are facing each other.) Level C Main Concepts: Bridges come in many designs, and must be strong and sturdy to handle heavy traffic. Piers help give bridges support. Some shapes support weight better than others. Vocabulary Answer: Eads Bridge The Eads Bridge is a combined road and railway bridge over the Mississippi River at St. Louis, connecting St. Louis and East St. Louis, Illinois. The bridge is named for its designer and builder, Captain James B. Eads. was the first steel bridge in the U.S. It uses arches and trusses. Have your students carefully follow the arrow clues to find the missing letters. Explain that some letters need to be filled in before they can find others. Some letters even follow a trail. Eads Bridge, built by Jonathan Buchanan Eads, opened for traffic in 1874 in St. Louis and spans the Mississippi River Mississippi River River, central U.S. It rises at Lake Itasca in Minnesota and flows south, meeting its major tributaries, the Missouri and the Ohio rivers, about halfway along its journey to the Gulf of Mexico. . Weekly Lab Explain that piers help hold up a bridge and make it strong. Ask your students if they think these index card "piers" can support some lightweight books. Have them first guess which of these shapes they think will be the strongest. (Let them experiment placing the cards in different directions, close together, far apart, etc.). Have them see how many books each shape can hold and which shape worked the best. (The V-fold is usually less stable than the others. It is most stable when the folded edges are facing each other.) Weekly Problem Answers: Left to right: Warren--Green, Purple, Red, Blue (repeated 4 times) and Burr--Blue, Green, Purple, Green, Purple, Green, Purple, Red, Blue, Red, Blue, Red, Blue, Green. Have your students color in the color key first. Point out that all the triangles point in different directions. Triangles are a very rigid geometric shape which adds to the strength of a truss bridge. Many of these criss-cross truss designs are named after the engineers who first patented them. Writing for Science Bridge builders must work at great heights, sometimes as tall as a 100-story building. There are so few people who are able to spin the cables at the tops of suspension towers, that skilled teams fly around the world from one job to another. Painters and maintenance workers also face the same dangers. Ask them to imagine being 1000 feet in the air with the wind gusting and blowing, while trying to remove a rusty bolt or paint a bridge. Have them think about the qualities a person would need to do this job. Challenge Your students' book stacks should be flat and equal in height. Have them place the pennies midway between the books. Pennies should be added until the paper sags or the pennies fall. Make sure that the bottom edges of the paper arch flare outward and are not curled under. If they are curled inward, their arch will collapse quickly. The arch is a stronger shape than the flat beam, because it better distributes the weight of the pennies--down the sides of the arch. Puzzle “Puzzle solving” redirects here. For the concept in Thomas Kuhn's philosophy of science, see normal science. A puzzle is a problem or enigma that challenges ingenuity. Answers: 1) e 2) c 3) a 4) d 5) b. Tell them to choose the name that best fits. Have them refer back to the front page, if needed. Level D Main Concepts: Bridges come in many designs, and use different ways of distributing weight, from beams, to cables, to arches. Some shapes are better suited to support heavy loads than others. Vocabulary Answers: a) span b) arch c) design d) truss e) cables f) suspension, London and Golden Gate. Have your students refer back to the words in bold print on the front page, if needed. Weekly Lab Your students' book stacks should be flat and roughly equal in height. Have them place the pennies midway between the books. Pennies should be added until the paper sags or the pennies fall. Make sure that the bottom edges of the paper arch flare outward and are not curled under. If they are curled inward, their arch will collapse quickly. The arch is a stronger shape, because it better distributes the weight of the pennies--down the sides of the arch. At 15 cm, the flat beam bridge will hold fewer pennies. Ask how the increased distance affects the arch. Encourage them to try folding the flat paper in different ways to strengthen it. Have them retest re·test tr.v. re·test·ed, re·test·ing, re·tests To test again. n. A second or repeated test. their new designs. Weekly Problem Answers: Left to right: Warren--Green, Purple, Red, Blue (repeated 4 times) and Burr--Blue, Green, Purple, Green, Purple, Green, Purple, Red, Blue, Red, Blue, Red, Blue, Green. The Warren truss For the Warren-type truss bridge, see . Warren Errol Truss (born 8 October 1948), is an Australian politician. He has been a National Party member of the Australian House of Representatives since March 1990, representing the Division of Wide Bay, Queensland. has more triangles (16) than the Burr burr (bur) bur. burr n. Variant of bur. burr 1. a plant seed capsule carrying many hooked structures which catch in animal coats thus promoting dissemination of the plant. (14). Triangles are a very rigid geometric shape, which adds to the strength of a truss bridge. Many of these criss-cross truss designs are named after the engineers who invented them. Writing for Science Bridge builders must work at great heights, sometimes as tall as a 100-story building. There are so few people who are able to spin the cables at the tops of suspension towers, that skilled teams fly all around the world from one job site to another. Painters and maintenance workers also face the same dangers. Ask your students to imagine being 1000 feet in the air with the wind gusting and blowing, while trying to remove a rusty bolt or paint a bridge. Have them think about the qualities a person would need to do this job. Challenge Answer: Eads Bridge was the first steel bridge in the U.S. It uses arches and trusses. Have your students carefully follow the arrow clues to find the missing letters. Explain that some letters need to be filled in before they can find others. Some letters even follow a trail. Eads Bridge, built by Jonathan Buchanan Eads, opened for traffic in 1874 in St. Louis and spans the Mississippi River. Puzzle Answers: 1) f 2) c 3) d 4) a 5) e 6) b. Tell your students to choose the bridge that best fits each name. Have them refer back to the front page for descriptions of these bridges. Level E Main Concepts: Bridge materials and styles must fit the place where the bridge is to be built, the load it is designed to carry, and the stresses it must handle. Different geometric shapes This is a list of geometric shapes. Generally composed of straight line segments
Vocabulary Answer: Eads Bridge was the first steel bridge in the U.S. It uses arches and trusses. Have your students carefully follow the arrow clues to find the missing letters. Explain that some letters need to be filled in before they can discover others. Some letters even follow a trail. Eads Bridge, built by Jonathan Buchanan Eads, opened for traffic in 1874 in St. Louis and spans the Mississippi River. Weekly Lab Your students' book stacks should be flat and equal in height. Have them place the pennies midway between the books. Pennies should be added until the paper sags or the pennies fall. Make sure that the bottom edges of the paper arch flare outward and are not curled under. If they are curled inward, their arch will collapse quickly. The arch is a stronger shape, because it better distributes the weight of the pennies--down the sides of the arch. At 15 cm, the flat beam bridge will hold fewer pennies. Ask how the increased distance affects the arch. Encourage them to try folding the arched paper in different ways to try and strengthen it. Have them retest these new designs. Explain that many bridges use a combination of designs to increase their strength. For the arch and beam design in Step 5, they may need to add some more books. This will increase the height of their stacks, so the sheet of paper will lay flat across the top of the arch. It is alright Alright is an alternative spelling of "all right". It is usually used to indicate that something is good but not great (so-so): "The play was alright." It is also used as an expression of great pleasure: "We won the championship! Alright!" for the flat sheet to be slightly raised above the books, as the arch will compress a bit when the pennies are added. The combined arch and beam design will usually hold about twice the load of the arch alone. Weekly Problem Answers: Left to right: Warren--Green, Purple, Red, Blue (repeated 4 times). Burr- Blue, Green, Purple, Green, Purple, Green, Purple, Red, Blue, Red, Blue, Red, Blue, Green. The Warren truss has more triangles (16) than the Burr (14). B) The 19 Burr trusses with 266 triangles would have more triangles than the 256 in the 16 Warren trusses. Triangles are a very rigid geometric shape which adds to the strength of a truss bridge. Many of these criss-cross truss designs are named after the engineers who first patented them. Writing for Science Bridge builders must work at great heights, sometimes as high as a 100-story building. There are so few people who are able to spin the cables at the tops of suspension towers, that skilled teams fly all around the world from one job site to another. Painters and maintenance workers also face the same dangers. Ask your students to imagine being 1000 feet in the air with the wind gusting and blowing, while trying to remove a rusty bolt or paint a bridge. Have them think about the qualities a person would need to do this job. Challenge The number of books your students will need to bridge the open space will depend on the size and weight of the books used. Their building surface should be flat. You can also have them build their cantilever bridges
Puzzle Answers: 1) g 2) c 3) e 4) a 5) f 6) d 7) b. Tell your students to choose the bridge that best fits each name. Have them refer back to the front page for descriptions of these bridges. Level F Main Concepts: Bridge materials and styles must fit the place where the bridge is to be built, the load it is designed to carry, and the stresses it must handle. The 2 kinds of stresses are compression and tension. Weekly Lab Part A: See TN Level E--WEEKLY LAB. Part B: The number of books your students will need to bridge the open space will depend on the size and weight of the books used. Their building surface should be flat. You can also have them build their cantilever bridges on the floor rather than on chairs or desks. The higher building platform will provide for a more dramatic visual effect, but keep in mind that the books are likely to collapse and be noisy. Have them try this activity again, increasing the distance. Weekly Problem Answers: 1) 16,896,000 pounds (which is 8448 tons) 2) The Quebec Bridge is about 100 feet longer (545.5 x 3.3 = 1800.15 ft.). 3) 72 x 8375 = 603,000 tons + 38,390 = 641,390 tons. Writing for Science Cable spinners Spinners can refer to:
attentiveness, heed, regard to details, like sights and sounds. Challenge Answers: 1) C 2) T 3) T 4) C 5) C 6) T 7) C 8) T. Puzzle Answer: Eads Bridge was the first steel bridge in the U.S. It uses arches and trusses. Have your students carefully follow the arrow clues to find the missing letters. Explain that some letters need to be filled in before they can discover others. Some letters even follow a trail. Eads Bridge, built by Jonathan Buchanan Eads, opened for traffic in 1874 in St. Louis and spans the Mississippi River. Helpful Sources for Planning your Science Weekly Classroom Activities Recommended Resources * Brown, David J David J. Haskins (b. April 24, 1957, in Northampton, England) is a British alternative rock musician. He was the bassist for the seminal gothic rock band Bauhaus. Life and work . Bridges. New York New York, state, United States New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of : MacMillan Publishing Co., 1993 * Darling, David. Spiderwebs to Skyscrapers. New York: Dillon Press, 1991 * Kaner, Etta. Bridges. Tonawanda, NY: Kids Can Press, 1997 * Kline, Michael. Bridges: Amazing a·maze v. a·mazed, a·maz·ing, a·maz·es v.tr. 1. To affect with great wonder; astonish. See Synonyms at surprise. 2. Obsolete To bewilder; perplex. v.intr. Structures to Design, Build & Test (Kaleidoscope kaleidoscope (kəlī`dəskōp), optical instrument that uses mirrors to produce changing symmetrical patterns. Invented by the Scottish physicist Sir David Brewster in 1816, the device is usually a hand-held tube, a few inches to as much Kids). Charlotte, VT: Williamson Publishing, 1999 * Mann, Elizabeth. The Brooklyn Bridge: A Wonders of the World Various Wonders of the World lists have been compiled over the ages in order to catalogue the most spectacular natural and manmade constructions. The Seven Wonders of the Ancient World is the first known list of remarkable manmade creations of classical antiquity, and was based on Book (Wonders of the World) New York: Mikaya Press, 1996 * Robbins, Ken. Bridges. New York: Dial Books, 1991 * Salvadori, Mario. The Art of Construction: Projects and Principles for Beginning Engineers and Architects. Chicago: Chicago Review Press, 1990 Internet Resources PBS PBS in full Public Broadcasting Service Private, nonprofit U.S. corporation of public television stations. PBS provides its member stations, which are supported by public funds and private contributions rather than by commercials, with educational, cultural, NOVA--test yourself on the 4 types of bridges, plus links to other bridge activities--http://www.pbs.org/wgbh/nova/bridge How Stuff Works--How Bridges Work--http://www.howstuffworks.com/bridge.htm Building Big from PBS--http://www.pbs.org/wgbh/buildingbig/bridge/index.html Bridge Watching for Beginners--http://www.media.uwe.ac.uk/masoud/projects/bridges/bridges.htm Bridge Photo Gallery--http://www.bridgesite.com/bridgephoto.htm Longest Bridges--http://www.hut.fi/Units/Departments/R/Bridge/longspan.html The Golden Gate Bridge--http://www.goldengatebridge.org Facts and History of the Brooklyn Bridge--http://www.nycroads.com/crossings/brooklyn Learn How Earthquakes Affect Bridges--http://www.ecs.csun.edu/~ceam/ShakeZone.htm Materials Needed for Issue 7--Terrariums Pre-A, A, B, C, D--plastic or glass containers with lids, rocks or gravel gravel, particles of rock, i.e., stones and pebbles, usually round in form and intermediate in size between sand grains and boulders. Gravel is composed of various kinds of rock, the most common constituent being the mineral quartz. , potting soil, a variety of small plants, spray bottles A Spray Bottle is a bottle that can squirt, spray or mist fluids. A common use for spray bottles is dispensing cleaners, cosmetics, and chemical specialties. While spray bottles existed before the middle of the 20th century, they used a rubber bulb, which was squeezed; the , crayons, leafy leaf·y adj. leaf·i·er, leaf·i·est 1. Covered with or having leaves. 2. Consisting of leaves: Spinach is a leafy green vegetable. 3. Similar to or resembling a leaf. houseplants in pots, tape, clear plastic bags E, F--plastic or glass containers with lids, rocks or gravel, activated charcoal Charcoal, Activated Definition Activated charcoal is a fine black odorless and tasteless powder made from wood or other materials that have been exposed to very high temperatures in an airless environment. , potting soil, vermiculite ver·mic·u·lite n. Any of a group of micaceous hydrated silicate minerals related to the chlorites and used in heat-expanded form as insulation and as a planting medium. , a variety of small plants, spray bottles, houseplants with broad leaves and thin grassy grass·y adj. grass·i·er, grass·i·est 1. Covered with or abounding in grass. 2. Resembling or suggestive of grass, as in color or odor. Adj. 1. leaves, tape, clear plastic bags |
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