Awesome ArchBy Cambridge Dragons

Teyahnie

DonaRaye

Malika

Clara

Claudia

Helped By

Shannon andLuba

Overview• Goals

• Design Process

• Prototypes

• Final Design

• Building

• Math and Science

• Types of Bridges

Goals• Decide on topic and

final design• Work as a team• Learn woodshop

and computer skills• Finish on or ahead

of time• Stay within budget

Design Process• Brainstorm

• Optical illusions• Amusement park • Bridges

• Topic selection• Talk with client

• Types of bridges• Suspension• Arch• Cable Stay• Draw• Truss

• Research/prototypes

Prototype #1

• Paper bridges• Invented different

bridges to test strength

Prototype #2

• Cardboard• To figure out

dimensions relative to exhibit space

Prototype #3

• Wood• To experiment with

large model• To get accustomed to

working with wood

Prototype #4

• Foam• To test our own

shapes of arches

• To prototype the actual bridge

Final Design

• A flat-topped arch that kids can assemble and walk on

• Pictures of famous bridges

• Text about the forces acting on bridges

Some Bridge Vocabulary• Abutment: A concrete structure used for support at

either end of a bridge, receiving the thrust from the ends of an arch. The abutment resists the compression from the arch.

• Arch: A curved structure which supports weight at its center by distributing compression down to the ground at its end.

• Compression: The effect of a force, which tends to shorten an object in the direction of the force.

• Keystone: The central wedge-shaped block at the top of an arch that holds the other pieces in place.

• Tension: The effect of a force, which tendsto lengthen an object by pulling it apart.

Building and Materials• Construction Steps

• Sketches and Hand-drawings

• Learning to use tools• Paper and foam models• Cutting, sanding,

assembling, staining pieces

• Materials• Maple Appleply wood• Nails, screws and glue• Stains and polyurethane

Working in the Woodshop

• Transfer design to wood and cut with saber saw.

• Assemble pieces with drills and the screw guns.

• Hand and power sanding to smooth edges and sides.

Final Steps•Attach supports to base.

• Color stain each piece.

• Build the center template.

Math We’ve Learned and Used

• Fractions

• Drawing to scale

• Angles

• Volume + Area

• Calculated circumference

r= radiusCircumference = 2r

    

Science• Forces

• Force = Mass x Acceleration

• Tension• Compression• Load

• Material Science• Modulus of Elasticity• Failure/Fracture

Dimension design using AutoCAD

Examples of Bridges

• Arch• Suspension• Cable Stay• Truss• Drawbridge

Arch Bridge• Can be combined

with other types• Each piece of an

arch is used to support the load

• An arch uses the force of compression

               

                     

Suspension Bridge

• Spans long distances over water

• Cables act in tension to support the load

• Cables connect from the bridge deck to the main cables

Cable Stay• Spans long distances • Cables connect from

the bridge deck to the towers

• Cables act in tension to support the load

• Towers act in compression

                                   

                               

Truss Bridge• Members act in both tension and compression

• Triangles are the main shape

• Is combined with other bridge styles

Drawbridge

• Trusses are the main shape

• Movable decks to allow ships to pass

• Shorter towers used• Spans short

distances

Special thanx to…..