THE WONDERFUL WORLD OF BRIDGES BY VICTORIA CANNON

TYPES OF BRIDGES ARCH SUSPENSION CABLE STAYED GIRDER CANTILEVER

The Physics Behind Bridges Compression -a force that acts to compress or shorten the thing it’s acting upon Tension -a force that acts to expand or lengthen the thing it’s acting on

Stress –a measure of the total internal forces acting within a body as a result of external applied and body forces Strain-measure of deformation A bridge should be able to withstand the compression and tension, stress and strain with a minimum of buckling or snapping It does this by dissipating or transferring the forces

                                                             GIRDER Is basically a bridge built atop girders placed upon bride abutments and foundation piers Oldest type of bridge Rolled steel, plate, concrete, box, I-beam, pi, T shaped girder bridges Most common, basic

NOTORIOUS GIRDER King Street Bridge, Melbourne, Australia Connecting King Street to Kingsway July 10, 1962, one span collapsed under the weight of a 47 ton semitrailer due to brittle fracture

CANTILEVER A modified form of the beam bridge with the support being placed in the middle of the span Like a diving board Can span wide spaces and be built without the need for expensive foundation piers

NOTORIOUS CANTILEVER The Quebec Bridge In both instances faulty calculations and poor materials were the cause 1907-killed 76 workmen 1908-killed 11 workmen Girders were misaligned and one of the four rocker arms failed

Arch Second oldest type Well suited for stone Doesn’t require a pier, so can span rivers and valleys Has a high resistance to bending forces Four common types: Hinge-less Two hinged Three hinged Tied arch

FAMOUS ARCH The Meiwa 137m Located in Edogawa, Japan Completed in 1992 Spans the Shinnaka River Braced Rib Arch 137m Completed in 1992 Used 784ft of steel

SUSPENSION Allows for the longest spans Extremely strong yet flexible Vulnerable to wind                                                             

FAMOUS SUSPENSION AKASHI KAIKYO BRIDGE Also known as the “Pearl Bridge” spans 1,991m (world’s largest) May 1986-April 5, 1998 23,000 cars per day Cost $5 billion dollars $20.00 toll Ferries used to cross the stormy Akashi Strait until two capsized killing 168 children. Bridge was built as a result.

NOTORIOUS SUSPENION The Point Pleasant/Silver Bridge Spanned the Ohio river connecting Point Pleasant, West Virginia to Kanauga, Ohio Made of carbon steel Dec 15, 1967, a heavy Christmas rush put extra stress upon the 39 year old carbon steel bridge causing a cleavage fracture in one of the “eyebars,” followed by a fracture near the pin. Took 1 minute to collapse completely. 46 dead, 9 injured.

Cable Stayed Consists of one or more columns with cables supporting the bridge deck Is ideal for lengths between that of cantilever and suspension bridges Comes in a mono, harp, fan and star design

FAMOUS CABLE STAYED Sunshine Skyway Bridge, St. Petersburg and Bradenton, Florida Completed in 1987 $244 million 29,040ft

Bridges in Literature The Bridge by Iain Banks

Bridges in the Media A Bridge Too Far (1977) Received 7.3 out of 10 stars from the Internet Movie Database