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Spanning the history of. Bridges. Natural Occurrences. Earliest examples. The Roman Arch – 1 st and 2 nd C. AD. Early civilizations. Mostly found in Europe (12 th -16 th C) Used for defense for water passages. medieval bridges. Located in England First iron bridge, finished in 1779.
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Spanning the history of Bridges
Natural Occurrences Earliest examples
The Roman Arch – 1st and 2nd C. AD Early civilizations
Mostly found in Europe (12th-16th C) Used for defense for water passages medieval bridges
Located in England First iron bridge, finished in 1779 New Materials
Let’s check out the top 24 bridges according to CNN-Travel. http://travel.cnn.com/explorations/none/24-worlds-most-amazing-bridges-062644 Famous bridges
Beam • Single beam sits upon piers • Requires support from underneath • Spans less than 250 feet due to support needed Types of bridges
Truss • Based on the support structure of triangles • Straight steel pieces, do not bend, span farther • Cantilever…(similar to a diving board) Types of bridges
Arch • Natural strength • Some do not require mortar • The arch squeezes, send force to abutments Types of bridges
Suspension • Farthest spanning bridge • Anchored at ends, compression on towers • Often have a truss system below to prevent bends Types of bridges
What is a Truss? • A structure composed of members connected together to form a rigid framework. • Usually composed of interconnected triangles. • Members carry load in tension or compression.
Component Parts Support (Abutment)
Types of Structural Members These shapes are called cross-sections.
Types of Truss Connections Pinned Connection Gusset Plate Connection Most modern bridges use gusset plate connections
2nd period • Laszlo / Tommy / Colin • Monica / Milad / Ezra • Carlos / Tim / • Alex / Kaitlyn / Chris • Alex / Christian / Juan • Brandon / Bryan • Noah / Melody / Brandon • Terique / Jose / Dartanyen • Ansley / Kyndall / • Luke / Connor • Matt / Kellie / • Taylor / Zoe
Popsicle sticks (50) Paper clips (20) 4 plastic solo cups Picture hanging wire (2’) 5 10” long yarn 10 pipe cleaners 2 8.5x11 card stock pages Toothpicks (50) Hot Glue (3 sticks of hot glue) 1’ of duct tape Your assignment • Span a 1’ gap • Must be 7” wide for A weighted base test (the deck of the bridge) • YOU MUST BRING IN YOUR MATERIALS! DUE ON FRIDAY! 2-22! BEGINNING OF CLASS!