Postgraduate textbook. Учебное пособие
.pdfText 10. CIVIL ENGINEERING
Civil engineering is the oldest and one of the most highly respected of all the engineering disciplines. It is a traditional industry, by its nature. From the very beginning man has been a builder and his creative ability and skilful craftsmanship are what the modern civil engineering industry is founded on. Today these traditional skills are coupled with the entire modern technology and thinking available to enable civil engineers to carry out their work to the highest of standards.
The traditional background of the industry presents, however, some problems. First of all, it is often perceived as old fashioned and reluctant to fully come to terms with the business world today. But it is obvious that new ideas cannot be implemented until they have been tried, proved and tested. So, if new management techniques are not considered and adopted, there would be a loss in competitive advantage, a vital factor in a highly competitive industry.
That is why it is necessary to ascertain the importance and relevance of management training in the construction industry. People have been managing companies ever since companies came into existence. It is necessary to manage a company effectively and efficiently as well as to produce high quality goods. It is especially important nowadays when construction work is limited and construction companies have to cut margins. Therefore, the effective management of an organization has become an art form in itself.
Civil engineering is a business and its survival is in making a profit. And it is the success of the «team» that is important. The team could be made up of engineers, quantity surveyors, estimators, planners, QA managers; personnel and computer specialists; all form an integral and equally important part of the business. Engineers may not grow into managers, but they must be trained for this role.
But it is a recognized fact that construction managers do not come into being by themselves. The training of graduate engineers in the construction industry at present consists of the undergraduate training within tertiary education, and postgraduate training within
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the industry itself. Although the number of hours devoted to teaching managements is increasing at educational establishments, graduates are still not adequately prepared for industry. Further training within the industry is varied and dependent on many factors such as the needs of the company, size of the company, and current health of the industry.
Management and management training within the construction industry is varied and is dependent on the sector, consulting or contracting, within which an engineer operates. It is necessary to take into consideration the attitudes of civil engineers and their companies towards modern management practices.
Construction managers are moving rapidly to meet the challengers of a modern business world and are making full use of the tools available. Consultants are a little behind in their attitudes to modern management but are improving; they have not yet realized the full potential of management training.
The alteration of construction industry attitude towards management practice would appear to stem from the business market within which a company is going to operate.
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Text 11. CONSTRUCTION
From the pyramids of Egypt to the international space station, construction industry has always faced the challenges of the future – advancing civilization and building our quality of life. Today, the construction industry is undergoing vast changes – the technological revolution, population growth, environmental concerns, and more.
Modern construction industry is a high hazard industry that comprises a wide range of activities involving construction, alteration, and/or repair. Construction is a process that consists of the building or assembling of infrastructure. Houses, apartments, factories, offices, schools, roads, and bridges are only some of the products of the construction industry.
This industry’s activities include the building of new structures, including site preparation, as well as additions and modifications to existing ones. The industry also includes maintenance, repair, and improvements on these structures.
The construction industry is divided into three major segments. Each of them requires a unique team to plan, design, construct and maintain the project.
1)The construction of buildings. This segment includes contractors, usually called general contractors, who build residential, industrial, commercial, and other buildings.
2)The Heavy and Civil Engineering Construction. This segment comprises establishments whose primary activity is the construction of entire engineering projects (e.g., highways, dams, bridges, tunnels, and other projects related to the infrastructure), and specialty trade contractors, whose primary activity is the production of a specific component for such projects. Specialty trade contractors in Heavy and Civil Engineering Construction generally are performing activities that are specific to heavy and civil engineering construction projects and are not normally performed on buildings.
3)Industrial construction. Specialty trade contractors perform specialized activities related to all types of construction such as carpentry, painting, plumbing, electrical work.
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The construction of buildings is considered to be an ancient human activity. It began with the purely functional need for a controlled environment to moderate the effects of climate. The earliest practices of building construction may have commenced between 4000 and 2000 ВС in Ancient Egypt and Mesopotamia (Ancient Iraq) when humans stopped their nomadic existence, thus causing a need for the construction of shelter. The most exiting example of large structure constructions are the Pyramids in Egypt.
Other ancient historic examples of building constructions include the Parthenon by Iktinos in Ancient Greece, the Appian Way by Roman engineers, the Great Wall of China and the stupas constructed in ancient Sri Lanka. The Romans developed civil structures throughout their empire, including especially aqueducts, insulae, harbours, bridges, dams and roads.
Modern methods of construction are more complicated than in early history of mankind. Today’s professional builders understand building science and know how to build a house that not only looks good, but also well constructed and great to live. New houses are bright and comfortable all year-round, and take full advantage of the many advances in building products, materials and technologies.
Another most important change that has occurred during the modern time all over the world is that the process of construction has been steadily moving away from the building site. Modern methods of construction involve the manufacture of buildings with potential benefits such as faster construction, fewer housing defects, and reductions in energy use and waste.
Typically modern methods of construction involve the manufacture of buildings parts off-site in a specially designed factory. The two main products of modern methods are: 1) panels, including ready-made walls, floors and roofs, which are transported to the site and assembled quickly, often within a day; 2) modules – ready-made rooms, which can be pieced together to make a whole house or flat. Modules are used most frequently for bathrooms or kitchens, where all the fittings are added in the factory.
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In Europe modern methods of construction also include innovative site-based methods, such as use of concrete moulds. The components are made in factories to precise specifications and then shipped to building sites where trained building crews install them.
The benefits of using such pre-manufactured components are numerous. Prefabricated components can be brought in as they are needed and installed immediately. Furthermore, these materials and products are manufactured under strict quality control and confirm to construction standards. A range of materials is used for construction of buildings, the most common being wood, steel and concrete, although many houses have a brick outer layer and so look like traditional houses.
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Text 12. NATURE OF THE CONSTRUCTION INDUSTRY
Houses, apartments, factories, offices, schools, roads, and bridges are only some of the products of the construction industry. This industry’s activities include work on new structures as well as additions, alterations, and repairs to existing ones. The construction industry is divided into three major segments. Construction of buildings contractors, or general contractors, builds residential, industrial, commercial, and other buildings. Heavy and civil engineering construction contractors build sewers, roads, highways, bridges, tunnels, and other projects. Specialty trade contractors are engaged in specialized activities such as carpentry, painting, plumbing, and electrical work.
Construction usually is done or coordinated by general contractors, who specialize in one type of construction such as residential or commercial building. They take full responsibility for the complete job, except for specified portions of the work that may be omitted from the general contract. Although general contractors may do a portion of the work with their own crews, they often subcontract most of the work to heavy construction or specialty trade contractors.
Specialty trade contractors usually do the work of only one trade, such as painting, carpentry, or electrical work, or of two or more closely related trades, such as plumbing and heating. Beyond fitting their work to that of the other trades, specialty trade contractors have no responsibility for the structure as a whole. They obtain orders for their work from general contractors, architects, or property owners. Repair work is usually done on direct order from owners, occupants, architects, or rental agents.
A civil engineering degree prepares you for work in the construction industry as well as in the business, management and financial sectors.
Job options of a civil engineer: Building control surveyor; Consulting civil engineer; Contracting civil engineer; Site engineer; Structural engineer; Water engineer.
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Jobs where the speciality of a civil engineer would be useful include: Building services engineer; Engineering geologist; Environmental consultant; Patent attorney; Quantity surveyor.
Remember that many employers accept applications from graduates with any degree subject, so don't restrict your thinking to the jobs listed here. Securing some kind of work experience is crucial. Employers place great importance on experience, and it will also give you an insight in the working practices of an engineering firm.
If your course does not include an industrial placement, look for relevant summer work experience and placements. Any kind of role in a construction or civil engineering setting will allow you to build your understanding of issues related to the planning and execution of projects. Use this experience to expand your knowledge and to develop contacts and network.
Casual, hands-on construction work and administrative jobs may be available, but many employers offer structured work experience opportunities.
Civil and structural engineers work in a range of sectors, particularly the construction sector, on buildings of all kinds, transport and communications infrastructure. This includes bridges, roads, tunnels, canals and other large structures. They also work for employers involved in the production, storage and distribution of electricity, gas and water.
Civil engineers are employed by a range of contractors and consultancies and also work in-house for a variety of national and multinational organizations. There are many opportunities in the public sector, with local authorities, government departments and environmental organizations, where engineers are often involved in setting project specifications and drafting tender documents.
Civil engineers are in demand for their technical and subjectspecific knowledge and understanding. With a sound grasp of science, mathematics and technology, you can design, create and build structures efficiently, making best use of available resources and techniques. Through realistic construction-based group projects, you
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gain practical experience of applying your engineering judgement and working successfully with others.
The skills gained by studying civil engineering are also sought after by employers in many other job areas. These include a creative approach to problem-solving, critical thinking and the ability to interpret data, numeracy, IT and communication skills, analytical and decision-making abilities, and an awareness of ethical issues.
Most new graduates who enter professional training with a civil engineering company continue to study part time while working in order to achieve professional standards to become either chartered (CEng) or incorporated (IEng) engineers.
Civil engineering courses at postgraduate level allow students to develop specialist knowledge in a particular area, such as water management, earthquake engineering, maritime civil engineering, environmental engineering and a range of other general and specific options. It is possible to carry out research through an MRes, MPhil or Ph.D., or to do a taught Masters course in these areas.
More than half of civil engineering graduates in employment in the UK are working as civil engineers six months after graduating.
Almost 14 % of civil engineering graduates go on to further study or combine further study and work, often undertaking research into an area of particular interest from their undergraduate degree.
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Text 13. CONSTRUCTION AND BUILDING MATERIALS
Researchers at MIT are seeking to redesign concrete – the most widely used human-made material in the world – by following nature's blueprints. In a paper published online in the journal Construction and Building Materials, the team contrasts cement paste – concrete's binding ingredient – with the structure and properties of natural materials such as bones, shells, and deep-sea sponges.
As the researchers observed, these biological materials are exceptionally strong and durable, thanks in part to their precise assembly of structures at multiple length scales, from the molecular to the macro, or visible, level. From their observations, the team, led by Oral Buyukozturk, a professor in MIT's Department of Civil and Environmental Engineering (CEE), proposed a new bioinspired, «bot- tom-up» approach for designing cement paste.
«These materials are assembled in a fascinating fashion, with simple constituents arranging in complex geometric configurations that are beautiful to observe», Buyukozturk says. «We want to see what kinds of micromechanisms exist within them that provide such superior properties, and how we can adopt a similar building-block- based approach for concrete». Ultimately, the team hopes to identify materials in nature that may be used as sustainable and longer-lasting alternatives to Portland cement, which requires a huge amount of energy to manufacture.
«If we can replace cement, partially or totally, with some other materials that may be readily and amply available in nature, we can meet our objectives for sustainability», Buyukozturk says.
Co-authors on the paper include lead author and graduate student Steven Palkovic, graduate student Dieter Brommer, research scientist Kunal Kupwade-Patil, CEE assistant professor Admir Masic, and CEE department head Markus Buehler, the McAfee Professor of Engineering.
«The merger of theory, computation, new synthesis, and characterization methods have enabled a paradigm shift that will likely change the way we produce this ubiquitous material, forever», Bueh-
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ler says. «It could lead to more durable roads, bridges, structures, reduce the carbon and energy footprint, and even enable us to sequester carbon dioxide as the material is made. Implementing nanotechnology in concrete is one powerful example [of how] to scale up the power of nanoscience to solve grand engineering challenges».
From molecules to bridges. Today's concrete is a random assemblage of crushed rocks and stones, bound together by a cement paste. Concrete's strength and durability depends partly on its internal structure and configuration of pores. For example, the more porous the material, the more vulnerable it is to cracking. However, there are no techniques available to precisely control concrete's internal structure and overall properties.
«It's mostly guesswork», Buyukozturk says. «We want to change the culture and start controlling the material at the mesoscale».
As Buyukozturk describes it, the «mesoscale» represents the connection between microscale structures and macroscale properties. For instance, how does cement's microscopic arrangement affect the overall strength and durability of a tall building or a long bridge? Understanding this connection would help engineers identify features at various length scales that would improve concrete's overall performance.
«We're dealing with molecules on the one hand, and building a structure that's on the order of kilometers in length on the other,» Buyukozturk says. «How do we connect the information we develop at the very small scale, to the information at the large scale? This is the riddle».
Building from the bottom, up. To start to understand this connection, he and his colleagues looked to biological materials such as bone, deep sea sponges, and nacre (an inner shell layer of mollusks), which have all been studied extensively for their mechanical and microscopic properties. They looked through the scientific literature for information on each biomaterial, and compared their structures and behavior, at the nano-, micro-, and macroscales, with that of cement paste.
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