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The cable stayed bridge is an elegant, economical and efficient structure. Virtually unknown 40 years ago, these bridges have become increasingly important as their properties have been more fully understood. The idea of supporting a bridge deck with cables from one or two pylons has been around for a long time. To the author’s knowledge, the concept of cable-stayed bridges can be tracked back to the early 1600s when the Venetian Verantius built a wooden bridge supported with chain stays. In 1784 the carpenter C. J. Löscher designed a cable-stayed bridge with an approximate span length of 32 m and where the entire bridge was made out of wood, including the stays.
In the 19th century, the French engineer Navier studied several bridge systems supported by wrought iron chains. The results of his studies show that suspension bridges should in general be preferred over cable-stayed systems. From today’s point of view, it can be said with certainty that Navier’s final conclusions were wrong. However, at the time Navier was studying these different bridge systems, the knowledge and equipment for acheiving an even distribution of the load between all the cables - which is one of the key issues for cable-stayed bridges - were not available.
German engineers pioneered the design of cable-stayed bridges after World War II. They were challenged to find new, innovative, and inexpensive bridge designs to replace most of the river crossings on the Rhine which were destroyed during the war. Dischinger proposed designs, where the central span was supported by a suspension system and stay cables carried the outer parts. Dischinger’s combined solutions were never adopted for an actual bridge, but his studies had a big influence on the development of the true cable-stayed bridge system. It was not until the 1950s that Dischinger designed the first true cable-stayed bridge. The Strömsund Bridge (Sweden, 1955) had a main span of 183 m and two side spans of 74.7 m. Gimsing attributes the increase in cable-stayed bridge designs to the improved structural analysis tools that were available. The Germans further developed the design of cable-stayed bridges in the following decades and built several of them. The series of bridges across the Rhine River near Duisburg are examples of these pioneering German bridges.

Starting with a brief history, it addresses general design criteria and current technology, as well as static and dynamic analysis. The illustrations provide numerous examples of structures already built and document their critical parameters, including examples of outstanding structures that have recently been completed. The chapter dealing with stay technology has been thoroughly updated to take into account the new, better quality products available from cable suppliers. The results of extensive experimental investigations concerning cable stayed bridges with slender decks, mentioned briefly in the first edition, are also presented here. The state-of-the-art analysis, design and construction associated with this kind of structure is clearly described in this book, making it an invaluable tool for practicing engineers and for students. Cable Stayed Bridges provides an easy introduction to a new field in bridge construction and is the most comprehensive book available on the subject. Brief contents: Historical review; General design; Parametric study; Stay technology; Static design; Dynamic analysis; Examples of small and medium-span cable stayed bridges; Model tests of a cable stayed bridge with slender concrete deck.

A space frame or space structure is a truss-like, lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames usually utilize a multidirectional span, and are often used to accomplish long spans with few supports. They derive their strength from the inherent rigidity of the triangular frame; flexing load (bending moments) are transmitted as tension and compression loads along the length of each strut.

Most often their geometry is based on platonic solids. The simplest form is a horizontal slab of interlocking square pyramids built from alumunium or steel tubular struts. In many ways this looks like the horizontal jib of a tower crane repeated many times to make it wider. A stronger purer form is composed of interlocking tetrahedral pyramids in which all the struts have unit length. More technically this is referred to as an isotropic vector matrix or in a single unit width an octet truss. More complex variations change the lengths of the struts to curve the overall structure or may incorporate other geometrical shapes.

Space frames were independently developed by Alexander Graham Bell around 1900 and Buckminster Fuller in the 1950s. Bell's interest was primarily in using them to make rigid frames for nautical and aeronautical engineering although few if any were realised. Buckminster Fuller's focus was architectural structures and has had more lasting influence.

Space frames are an increasingly common architectural technique especially for large roof spans in modernist commercial and industrial buildings.

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