Empirical Information: Information that is based on observation and experience rather than theoretical knowledge.

Civil Engineering: The branch of engineering that deals with the design and construction of structures that are intended to be stationary, such as buildings, dams, and bridges. Among its subdivisions are structural engineering, dealing with permanent structures; hydraulic engineering, dealing with the flow of water and other fluids; and environmental/sanitary engineering, dealing with water supply, water purification, and sewer systems, as well as urban planning and design.

Mechanical Engineering: The branch of engineering that deals with machines and their uses.

Mining and Metallurgy: The branch of engineering that deals with extracting metal ores from the earth and refining them.

Chemical Engineering: The branch of engineering that deals with processes involving reactions among the elements, the basic natural substances. Petroleum engineering is a subdivision which deals specifically with processes involving petroleum.

Electrical and Electronic Engineering: The branch of engineering that deals with the effects and processes that result from the behavior of tiny particles of matter called electrons.

Nuclear Engineering: A modem branch of engineering that deals with the processes that result from breaking up some particles of matter.

Aqueduct: A structure that is used for transporting water over long distances.

Stress: Physical pressure or other forces exerted on an object. The force of gravity, the natural pull of the earth, for example, is one of the stresses that acts on an object. Silt: Sand or earth transported from one location by water and deposited as sediment at a second location.

Environmental Impact Study: A study that shows the effect a proposed structure will have on its surroundings: the air, water, human, animal, and plant life, for example. Such studies are now required for most major construction projects in the United States.

Vocabulary Practice

What does engineering mean?

What is a profession? Give some examples.

How does a railroad locomotive engineer differ from a professional engineer?

What is empirical information?

What does a civil engineer deal with?

What are some of the subdivisions of civil engineering? With what is each of them concerned?

What does a mechanical engineer deal with?

What does a mining and metallurgical engineer deal with?

What does a chemical engineer deal with? Name a subdivision of chemical engineering.

What do electrical and electronic engineers deal with?

What do nuclear engineers deal with?

What is an aqueduct?

What is stress?

Define silt.

What is an environmental impact study concerned with?

What does quantification mean?

The Engineering Profession

Engineering is one of the oldest occupations in the history of mankind. Indeed, without the skills that are included in the field of engineering, our present-day civilization could never have evolved. The first toolmakers who chipped arrows and spears from rock were the forerunners of modern mechanical engineers. His craftsmen who discovered metals in the earth and found ways to process and refine them were the ancestors of mining and metallurgical engineers. And the skilled technicians who devised irrigation systems and erected the great buildings of the ancient world were the civil engineers of their time. One of the earliest names that have come down to us in history is that of Imhotep, the designer of the stepped pyramid at Sakkara in Egypt about 3,000 B.C.

Engineering is often defined as the practical application of theoretical sciences, such as physics or chemistry, for the benefit of mankind. Many of the early branches of engineering, however, were based not on science but on empirical information, that is, information that depended on observation; and experience rather than theoretical knowledge. Many of the structures that have survived from ancient times, such as the aqueducts of Rome, exist because they were built with greater strength than modem standards require. But at least the Roman engineers were sure that buildings would last for a long time. Probably die oldest text in engineering is the work of a Roman architect and engineer named Vitruvius Pollio, who wrote a book in the first century B.C. about the engineering practices of his day. Many of the problems encountered by Vitruvius Pollio were similar to those that modern engineers still must confront.

The term civil engineering originally came into use to distinguish it from military engineering. Civil engineering dealt with permanent structures for civilian use, whereas military engineering dealt with temporary structures for military use. An example of the latter is the bridge built across the Rhine in 55 B.C. that is described in Julius Caesar's Commentaries on the Gallic War. A more appropriate definition of civil engineering is that it deals with the design and construction of objects that are intended to be stationary. In practice, this definition includes buildings and houses, dams, tunnels, bridges, canals, sanitation systems, and the stationary parts of transportation systems-highways, airports, port facilities, and roadbeds for railroads.

Civil engineering offers a particular challenge because almost every structure or system that is designed and built by civil engineers is unique. One structure rarely duplicates another exactly. Even when structures seem to be identical, site requirements or other factors generally result in modifications. Large structures like dams, bridges, or tunnels may differ substantially from previous structures. The civil engineer must therefore always be ready and willing to meet new challenges.

Since the beginning of the modem age in the sixteenth and seventeenth centuries, there has been an explosion of knowledge in every scientific field: physics and chemistry, astronomy and physiology, as well as recently evolved disciplines like nuclear and solid-state physics. One reason for this rapid increase in scientific knowledge was the development of the experimental method to verify theories. At least of equal importance has been the use of quantification, that is, putting the data from the results of experimentation into precise mathematical terms. It cannot be emphasized too strongly that mathematics is the basic tool of modem engineering.

As scientific knowledge increased, so did the practical applications. The eighteenth century witnessed the beginning of what is usually called the Industrial Revolution, in which machines began to do more and more of the work that previously had been done by human beings or animals. In the nineteenth century and in our own day, both scientific research and the practical applications of its results have progressed rapidly. They have given the civil engineer new and stronger materials; the mathematical formulas which he can use to calculate the stresses that will be encountered in a structure; and machines that make possible the construction of skyscrapers, dams, tunnels, and bridges that could never have been built before.

Another result of the explosion of knowledge was an increase in the number of scientific and engineering specialties. By the end of the nineteenth century, not only were civil, mechanical, and mining and metallurgical engineering recognized, but courses were also being offered in the newer specialties of electrical engineering and chemical engineering. This expansion has continued to the present day. We now have, for example, nuclear, petroleum, aerospace, and electronic engineering. Of course, many of these disciplines are subdivisions of earlier specialties-electronic engineering from electrical engineering, for example, or petroleum engineering from chemical engineering.

Within the field of civil engineering itself, there are subdivisions: structural engineering, which deals with permanent structures; hydraulic engineering, which is concerned with systems involving the flow and control of water or other fluids; and sanitary or environmental engineering, which involves the study of water supply, purification, and sewer systems. Obviously, many of these specialties overlap. A water supply system, for example, may involve dams and other structures as well as the flow and storage of water.

Many different kinds of engineers often work on large projects, such as space exploration or nuclear-power development. In the space program, for example, the launching pads and the rocket assembly and storage building at Cape Canaveral, Florida - the largest such structure in the world - are primarily the work of civil engineers. In a nuclear power plant, civil engineers are responsible for the design and construction of the plant itself, as well as the protective shielding around the nuclear reactor. In both these cases, however, the civil engineers work with specialists in aerospace, nuclear, and electrical engineering. In projects of this kind, the engineer is a member of a team that is often headed by a systems engineer who coordinates the contributions of all members of the team. Because teamwork is necessary in so many engineering projects nowadays, an important qualification for engineers is the ability to work successfully with other people.

Still another result of the increase in scientific knowledge is that engineering has grown into a profession. A profession is an occupation like law, medicine, or engineering that requires specialized, advanced education; indeed, they are often called the "learned professions." Until the nineteenth century, engineers generally were craftsmen or project organizers who learned their skills through apprenticeship, on-the-job training, or trial and error. Nowadays, many engineers spend years studying at universities for advanced degrees. Yet even those engineers who do not study for advanced degrees must be aware of changes in their field and those related to it. A civil engineer who does not know about new materials that have become available cannot compete successfully with one who does.

The word engineer is used in two ways in English. One usage refers to the professional engineer who has a university degree and an education in mathematics, science, and one of the engineering specialties. Engineer, however, is also used to refer to a person who operates or maintains an engine or machine. An excellent example is the railroad locomotive engineer who operates a train. Engineers in this sense are essentially technicians rather than professional engineers.

Engineers must be willing to undergo a continual process of education and be able to work in other disciplines. They must also adapt themselves to two requirements of all engineering projects. First, the systems that engineers produce must be workable not only from a technical but also from an economic point of view. This means that engineers must cooperate with management and government officials who are very cost-conscious. Therefore, engineers must accommodate their ideas to the financial realities of a project.

Second, the public in general has become much more aware, especially in the last ten years or so, of the social and environmental consequences of engineering projects. For much of the nineteenth and twentieth centuries, the attitude of the public could be summed up by the phrase, "Science is good." The most visible part of science was the engineering work. No one can avoid seeing the great dams, the bridges, the skyscrapers, and the highways that have created an impressive, engineered environment around us.

Nowadays, however, the public is more conscious of the hidden or delayed hazards in new products, processes, and many other aspects of civil engineering systems. For instance, new highways in the United States are no longer approved routinely; instead, highways and other similar projects must now undergo environmental impact studies to assess the project's effect on air pollution and other environmental concerns.

A recent news story which reported that the Egyptian government now permits public criticism of the Aswan High Dam underlines this concern. The Aswan Dam is one of the engineering wonders of modern times, but several undesirable effects have been noted. The dam has, for instance, blocked the flow of silt down the Nile, so that the fertility of the land below the dam has decreased. Nutrients that were once carried down the river have been held back by the dam, and consequently schools of fish that once thrived around the Nile Delta have gone elsewhere. Still another reported effect of the dam has been the increase of the salinity of the soil which is irrigated by the water behind the dam. These and other problems might have been prevented by more thorough studies before construction was undertaken.

In other words, engineers do not work in a scientific vacuum. They must consider the social consequences of their work. We have, after all, described engineering as a profession that makes practical application of the findings of theoretical science. Successful engineers must include in their definition of practical the idea that the work is also desirable and safe for society

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