Bridges: The Science and Art of the World's Most Inspiring Structures

The Brooklyn Bridge, London's Tower Bridge, Sydney's Harbour Bridge, San Francisco's Golden Gate--bridges can be breathtakingly monumental structures, magnificent works of art, and vital arteries that make life vastly easier.

In Bridges, eminent structural engineer David Blockley takes readers on a fascinating guided tour of bridge construction, ranging from the primitive rope bridges (now mainly found in adventure movies), to Roman aqueducts and the timber trestle railway bridges of the American West, to today's modern marvels, such as the Akashi-Kaikyo Bridge, which has the largest span in the world. Blockley outlines the forces at work on a bridge--tension, compression, and shear--and the basic structural elements that combat these forces--beams, arches, trusses, and suspensions (or BATS). As he does so, he explores some of the great bridges around the world, including such lesser-known masterpieces as the Forth Railway Bridge (featured in Alfred Hitchcock's The Thirty-Nine Steps), and describes some spectacular failures, such as the recent bridge collapse in Minnesota or the famous failure of the Tacoma Narrows Bridge in 1940. For instance, Blockley discusses the London's Millennium Bridge--the blade of light across the Thames--which displayed an alarming wobble when opened. He explains that when people walk, they not only exert force directly forward, but also exert a lesser force to the side, and the Millennium Bridge engineers did not consider this tiny lateral movement in their otherwise meticulous design. Amazingly enough, this minor omission caused a wobble severe enough to close the bridge for two years.

Bridge building is a magnificent example of the practical use of science. But as Blockley shows in this illuminating book, engineers must go beyond science, blending technical experience and creativity to build the spans that connect us all.

"In this fascinating exploration for lay readers, Blockley lucidly explains both the basic forces at work on every bridge — tension, compression, and shear — and the structural elements combating those forces: beams, arches, trusses, and suspension cables. He succeeds in his desire to 'read a bridge like a book.' Following fellow civil engineers and writers David Billington and Henry Petroski, Blockley makes clear that engineers as much as architects and scientists design bridges and that technology is not merely 'applied science.' The author provides an excellent history of bridge construction, from primitive rope bridges and Roman aqueducts to 19th- and 20th-century railroad bridges and contemporary achievements like Japan's Akashi-Kaiky Bridge, which has the largest central span of any suspension bridge. The author also discusses important bridge failures and the lessons learned from them, including the Minnesota I-35 bridge, and the less seriously damaged London Millennium Bridge, which was closed for two years after opening day's huge crowds caused wobbling. Blockley concludes that bridges do not merely transport people and goods but also 'help us express some of our deepest emotions.' Bold, insightful statements help make this a remarkable work. 50 b&w illus." Publishers Weekly (Starred Review) (Copyright Reed Business Information, Inc.)

David Blockley is an Emeritus Professor and Senior Research Fellow at the University of Bristol, England. He is a Fellow of the Royal Academy of Engineering, the Institution of Civil Engineers, the Institution of Structural Engineers, and the Royal Society of Arts. He was President of the Institution of Structural Engineers 2001-02.

1. Bridges are BATS: Why we build bridges

2. Underneath the Arches: Bridges need good foundations

3. Bending it: Bridges need strong structures

4. All Trussed up: Interdependence creates emergence

5. Let it all Hang Down: Structuring using tension

6. How Safe is Safe Enough? Incomplete science

7. Bridges built by people for people: Processes for joined-up thinking

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