Structures: bridge 360 building

Composite materials have been acclaimed as the Materials of the Future. A key question is whether composite materials will always remain the materials of the future or if the future is here. Advanced polymer composites, once destined for stealth military aircraft or aerospace uses, are beginning to be used in down-to-earth structures, such as bridges, buildings, and highways. However, there are still considerable impediments to wider use, and composite manufacturers need to make great strides in the development and manufacturing of composite materials. 

Corrosion is the deterioration of a metal by oxidation, such as the rusting of iron in moist air. The economic consequences of rusting are enormous It has been estimated that up to one-fourth of the iron produced in the United States is used to replace bridges, buildings, and other structures that have been destroyed by corrosion. (The raised dot in the formula Fe2C>3 H20 for rust indicates that one water molecule is associated with each Fe2C>3 in an undefined way.)... 

Since steel is the main structural material for bridges, buildings, and automobiles, controlling its corrosion is extremely important. To do so, we must understand the corrosion mechanism. Instead of being a direct oxidation process, as we might expect, the corrosion of iron is an electrochemical reaction, as illustrated in Fig. 11.17. 

It has been estimated that corrosion of cars, bridges, ships, the structures of buildings, and other metallic objects costs more than 100 billion dollars a year in the U.S. alone. For this reason, people have devised several means to minimize corrosion. One is simply to apply a coat of paint to seal out both air and moisture, but, because paint deteriorates, objects such as the ship s hull shown in Figure 21-15a must be repainted often. 

Oxyacetylene welding is used to repair metal structures, including bridges, buildings, and even the Statue of Liberty. Calculate AS° for the combustion of 1 mol of acetylene (C2H2). 

Since steel is the main structural material for bridges, buildings, and automobiles, controlling its corrosion is extremely important. To do so, we must... 

Most of this chapter has discussed bridges, with peripheral comments about other civil engineering structures. This is partly because most of the emphasis in the field of durability has been problems with bridges caused by chloride attack. Many of the discussions are relevant to all reinforced concrete structures. However, buildings are constructed to withstand less severe environments and conditions than bridges. There are also lower life expectations on buildings which may become obsolete before serious deterioration occurs. 

Blockley, David. Bridges The Science and Art of the World s Most Inspiring Structures. New York Oxford University Press, 2010. Written by a professor of engineering with a lay reader in mind discusses basic forces such as tension, compression, and shear, and bridge failures. Includes a comprehensive history of bridge building with fifty illustrations. 

A complex structural system, such as frame structures representing buildings, bridges or mechanical systems, can be assembled from components which are formulated as reciprocal structures. Reciprocal structures are those structures characterized by convex potential and dissipation functions (Stern, 1965). In this section, the concept of reciprocal structures is explained using simple spring-mass-damper-slider models shown in Figure 1. Mixed Lagrangian and Dissipation functions of such systems are derived for various structural components. 

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