Внеаудиторное чтение, 3 семестр
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Внеаудиторное чтение, 3 семестр





Внеаудиторное чтение, 3 семестр

Часть 1

Laboratories

There are several laboratories at the building department and the best of them is the laboratory of the Chair of Mechanics of Engineering. It is one of the best equipped laboratories in the institute and the students of almost all the departments have their practical training there.

The Laboratory of the Chair of Mechanics of Engineering

The laboratory conducts experiments to test strength of mate­rials. Through these experiments students get acquainted with such mechanical properties of materials as strength, hardness, plasticity, elasticity, shock resistance etc.

The laboratory also conducts experiments to check certain the­oretical statements.

To study mechanical behaviour of materials it is necessary to create stresses changing in time and conditions under which one can get that or another type of deformation.

All this is accomplished by means of testing machines of va­rious capacities the laboratory is equipped with. The laboratory has devices capable of producing deformations ranging in tension with stresses from 1 kg to 50 tons and in compression with stres­ses up to 300 tons. It also possesses devices testing materials for torsion, cold bending, impact fatigue as well as surface hardness.

When materials are tested deformations hardly ever reach the values that can be measured directly. As a rule the values are .exceedingly small and amount to thousandths of a millimeter.

For measuring such small deformations special sensitive extensometers are employed. These may be of mechanical, optical, and electric type, the last type being most widely used in the la­boratory.

There is also a small workshop providing the laboratory with test specimens. It also makes repairs of the testing machines when necessary.

The laboratory is subdivided into two separate parts, one hous­ing the machines for students work and the other being used by the science workers of the chair for their research.

The Laboratory of Hydraulics

The laboratory of hydraulics plays an important role in train­ing specialists at USTU-UPI.

The students of most specialities of the Mechanical, Chemical, Heat-Engineering, the Technology of Silicates and the Building departments (all specialities but the Architecture) are given prac­tical training in this laboratory. The laboratory is designed mainly for practical work in the subjects of "Hydraulics" and "Hydraulic Machines".

The laboratory and its equipment are used not only for student work but also for research conducted by science workers of various chairs of the university.

Hydraulic is the branch of science that deals with the laws it balance and motion of liquids in natural and artificial chan­nel structures and machines. It is a part of hydromechanics. The subject of hydraulics and hydraulic machines consists of two parts namely the theoretical part studying the laws of motion and balance of liquids and the practical part concerned with the application of these laws in solving various practical problems.



Methods of differential and integral calculus as well as the laws of physics and theoretical mechanics and some parts of "Strength of materials" form the basis of the subject of "Hydrau­lics and Hydraulic Machines".

The laboratory work and experiments are of great value when studying hydraulics because of the complexity of many hydraulic phenomena which are to be considered in solving certain engi­neering problems., Hydraulics like most sciences can develop only is a result of close combination of theory and experiment. That is why future engineers should acquire not only theoretical knowledge but the skill in conducting laboratory experiments as well. Besides, many phenomena referred to in lectures become clear only after direct observation in the laboratory conditions.

The 1aboratory is equipped with a reservoir, a pressure tank, a number of working pumps, with two systems of pressure con­duits of different diameters as well as with measuring tanks and receiving chutes. All these are fitted with special measuring devices.

The floor space of the laboratory and the chair is 354 sq. m. All the installations operate at a constant pressure in the following cycle: the reservoir — the centrifugal pump — the pressure tank— the installations-the reservoir.

The most important-laboratory experiments carried out by the students are:

1. The measuring of hydrostatic pressure in an enclosed space. In conducting, the work the students get acquainted with various kinds of devices used for measuring pressure and with the me­thods of their application.

2. An experiment showing the equation of Bernully.

3. The conditions (regimes) of motion of liquids. The work shows the difference in the laminar and turbulent flow of a liquid.

The students get to know the way of checking up the operation of hydraulic systems by of Reynolds criterion.

Some experiments show how to determine the coefficient ofhydraulic friction and the coefficients of losses arising in the flow passing through various local obstacles such as turns, valve and sudden narrowing and widening of a channel resulting in the change of either direction or magnitude of the flow or both.

Some other experiments help the students find out both the operation data of a centrifugal pump and the principles of its design and operation.

All these experiments enable the students to improve their knowledge of hydraulics as well as to get certain skill in making various experiments and in describing the results obtained during the work in a short but technically correct summary.

 

Architecture

Architecture is the art of building according to principles de­termined not only by the purposes the structure is to serve, but also by considerations of beauty and harmony.

The task of an architect is to design beautiful and comfortable apartment houses, public buildings and industrial enterprises. It is an important and honourable task

The word "architecture" comes from a Greek word "architecon" which meant the chief builder. It is the architect who is the first person to plan any building. He chooses the style and determines the size of the structure, its layout and architectural appearance suitable for the purpose.

The architect must coordinate the work of a big group of specialists concerned with the construction of a building (a sanitary engineer, a construction engineer, a planning expert and many others). Very often the skill and talent of the architect decide the success of the whole work.

The architectural speciality of Ural State Technical University trains not only painters who are able to create monuments, memorial parks and interiors of important big public buildings but engineers who can successfully solve different practical problems of construction and architecture.

The graduates of the chair of architecture work in various towns and cities of our country and abroad. Some of them are head architects of designing offices, and whole towns while the others are the authors of many civil and industrial construction designs.

The basis of the architectural speciality is architectural desig­ning which helps students to acquire practical knowledge of architecture from the very first year of their studies here such as volume and space, architectural elements of buildings and their shapes, proportions, tectonic structure and harmony as well as elements of architectural drawing. The would-be architects design first rather simple and further on more and more complicated structures.

Great attention is paid to the knowledge of monuments of classical architecture, the architecture of Ancient Egypt, Greece and Rome, the Renaissance as well as various modern styles both in our country and abroad.

In addition to special architectural subjects some general con­struction engineering disciplines are absolutely necessary for a future architect. These are:

1. Building materials.

2. Construction technology.

3. Footings and foundations.

4. Theory and designing of reinforced concrete, steel and tim­ber units.

5. Various elements of buildings such as:

a) precast and monolithic foundations;

b) bearing and curtain walls;

c) floors, stairs, windows, stained-glass panels, lanterns, roofs and so on.

The university gives the fundamentals of all these disciplines. The instruction is given by specialists highly qualified in the field of civil and industrial architecture and all branches of construc­tion engineering. The knowledge obtained at the institute will form a solid basis for the future practical work of the architect, for his fruitful creative work.

 

City Engineering

The engineer dealing with town planning and construction is confronted with a great variety of engineering problems. A rail­way engineer must know principally about railways; an electri­cal engineer must know about lightning, heating and power, a sanitary engineer must know water purification and about sewerage; but a city engineer should know about these and many other branches of engineering. Certain principles of city planning are now generally accepted and every town should have a com­prehensible plan comprising all information concerning streets, parks and public buildings; all public services, such as transpor­tation, lighting, heating and water supply; distribution of popu­lation and industries; the housing of people, sizes and type of houses, size of yards, distances to parks and so on. All this comes within the scope of activities of a city engineer.

 

Air Conditioning

The term air conditioning in its broadest sense means control of any or all the physical or chemical qualities of the air within a structure. More particularly, it includes the simultaneous control of temperature, humidity, purity of the air (dust, bacteria, odors, toxic gases, ionization) most of these factors affect in greater or lesser degrees human health or comfort. The term is broad enough to embrace what­ever other additional factors may be found desirable for maintain­ing the atmosphere of occupied spaces at a condition best suited to the physiological requirements of the human body.

 


Часть 2

Concrete

These days, a building's framework is as likely to be of reinforced concrete as of structural steel. Concrete is made by mixing together small stones, sand, cement, and wat­er in rotating drums. The mixture is tipped or piped into forms (wooden molds) of the shape required. The coarse stones used in the mix give the concrete its strength, the sand is needed to fill the gaps between the stones; and the cement (mixed with just enough water to make it into a paste) covers the surfaces of all solids and binds the entire mixture into a single mass.

The less water that is used in mixing the concrete, the denser and stronger it is when it has set. The difficulty here is that a dryish mix is not so easy to stir as one that is fairly wet and sloppy. So where a really strong concrete is essential, it is mixed with the necessary minimum of water, placed in the forms, and then vibrated, before it sets, by slowly "comb­ing" it with electrically vibrated bars. This both drives out any lingering pockets of air and ensures that the mix is thor­oughly even to make the concrete resistant to bending, engineers reinforce it.

They do this by putting bars of steel or miniature steel frameworks into the form-before the concrete mixture is poured-in just those places where the stress will be greatest. Hence the name "reinforced concrete". With such material an infinite variety of constructional shapes can be pro­duced, including "shells" and roofs in the shape of hyperbolic paraboloids. For these very modern structural items reinfor­ced concrete is used in thin sheets.

In an ordinary reinforced concrete beam, much of the concrete does little more than hold the steel in place. It can be used more effectively if, before the external load comes on, stresses are put into it. For instance, suppose that a rein­forced beam could be bent out of the straight by an inch, either upward or downward, before it developed serious cracks. Then, if we tighten up the reinforcement before any load comes on so as to bend the beam an inch upward, it would take twice as much load as before to bend it an inch downward. In other words, we can, by prestressing it in reverse, prepare the con­crete in advance to withstand the pressures and pulls that the external load will cause.

Concrete can be prestressed in two ways. In the first meth­od, the concrete is cast around stretched steel wires. When the concrete has set, the wires are released and compress the concrete as they contract. Such a method of prestressing pro­duces pretensioned concrete.

The other method is called post-tensioning. In the case of a beam, for example, the concrete is cast around polythene tubes through which, after the concrete has set, steel cables are drawn. These cables are anchored at one end of the beam, stretched by jacks, and then fixed at the other end of the beam. In their stretched position they give a built-in stress to the beam; and this too will be cancelled out when a load is applied.

In constructing a building, it is possible to cast the floors and walls as well as the framework directly on the spot where they are to stand. The building then forms a monolith-one large artificial stone composed entirely of concrete that has been shaped within wooden molds that fit together per­fectly. Thus, no sections have to be joined together later on. To cast all the parts in place, the builder has, of course, to use a great many forms; these are removed as soon as the concrete has set. Arid the concrete of each story must be given plenty of time to harden before work on the next story can begin.

In order to save time, the builder may prefer to use a num­ber of standardized concrete units. These can then be made in advance-that is, either the individual members can be pre­cast (and possibly prestressed), or whole sections of the build­ing can be prefabricated.

Precasting and prefabrication have made possible the speedy erection of buildings designed to use a great many standardized parts (such as window frames).

 

Types of Buildings

Types of buildings depend upon social formations and may be classified according to the role in the community. The types of buildings may be domestic, educational, office, industrial, recreational, etc. The type and the function of a building govern its design, building materials and techniques. But the common and necessary conditions are: (1) its suitability to use by human beings in general and its adaptability to particular human activities (2) the stability and permanence of its construction.

Speaking of residential construction we must say that the apartment houses are mostly built to suit urban condi­tions. Group housing provides home for many families and is at once public and private. The techniques of construction or the methods by which structures are formed from particular materials are influenced not only by the availability and character of materials but also by the total technological dev­elopment of society.

The evolution of techniques is conditioned by two factors: one is economic-the search for a maximum of stabil­ity and durability in building with a minimum of materials, labour and time; the other is expressive- the desire to pro­duce meaningful form. Techniques evolve rapidly when econom­ic requirements suggest new expressive forms or when the conception of new forms demands new procedures.

Large housing programs have tended to stimulate tech­nological change in the building industry. Craft operations at the building site are being replaced by mechanized operations at the factory and houses arc increasingly becoming assemblages of factory-made elements. Windows and doors, once made and fitted by carpenters at the site now arrive from a factory fitted and finished with hardware and glass, ready to be set in place. Modular design (i.e. design in which the elements are dimensioned in combinations of a fixed unit) has led to standardization of elements, interchangeability of parts and increased possibilities for mass production, with resultant economies. Awide variety of mass-produced elements from which substantial portions of the house can be assembled are now available. Examples are kitchen cabinets and mechanical equipment and window and door units. Entire apartment assemblages are available and are being used to an increasing extent. These techniques aim at a higher output of better structures at lower cost.

The high degree of mechanization and standardization is successfully achieved by reinforced concrete blocks and units. Reinforced concrete homes are produced by a variety of construction methods. Various methods of constructing reinforced concrete houses involve extensive use of large sections manufactured in heavily mechanized factories and erected at the site.

The built-in space of an apartment should be carefully thought of as well. The contemporary trend is expressed by joining the living and dining areas into a single space or by relating the kitchen and dining areas. It has become increasingly important as rooms that have become smaller should appear as spacious as possible. Therefore, there is a considerable trend toward built-in furniture. Rooms should be both efficient and visually satisfying. The extent of built-in cabinets must be determined. Drawers and shelves can often be concealed behind walls, freeing valuable floor space.

The windows and doors must look well from the inte­rior us well as from the exterior. Satisfactory functioning is also involved; windows must be sized and located for the best possible lighting and ventilation; as for electricity it should be mentioned that the electric load of most houses has increased enormously as standards of lighting rose and mechanical and household equipment multiplied. Great technological advances have been made in plumbing. Much progress has been made with respect to standardization and production of the elements of kitchen equipment.

 

Design of the Complete Town

In considering the design of a town or city we must always remember that the town must be always sited in a healthy position, free from dust, fogs, its layout must not encourage winds through urban spaces, and must not pollute its own atmosphere. It must provide proper standards of space and sunlight to its buildings and open spaces, and it must be possible to move about the town easily and without danger to life. Its parts must be so arranged that it is a convenient place for dwelling, working and playing.

Connected with these and many other technical prob­lems is the problem of economy. The problem must be thor­oughly examined which does not suggest that the cheapest scheme may be the best.

The town must work properly but it should also give pleasure to those who look at it. When we say that a town should be beautiful, we do not mean that it should have some fine parks and noble buildings, we mean that the whole of the environment, down to the most insignificant detail, should be beautiful.

If we examine a typical urban scene we see all kinds of objects like buildings, lamp posts, paving, posters, and trees. It is all of them, together with all the other kinds of objects that are found in the town, that are called the raw materials of a town design. Each ofthem down to the least important should be aesthetically satisfying.

The town designer must think of his raw materials in terms of time. Notthe time it takes to walk about them, although that is an important consideration, but their place in historical time, their effect on tradition, their immediate effect as contemporary objects, and their effect in future time.

All newdevelopment takes place in an existing environment. Thatenvironment has taken centuries to form and the design respect any features that have visual signifi­cance. It is more than vandalism to fall a tree that has taken years togrow, or to demolish a building of fine architectural

Desisting in terms of past time does not imply the imitationofthe existing environment but respect of the form, colour, texture, and general qualities of the exiting development. That which is being constructed is for immediate use which is not to suggest that there must be an attempt to ignore the past and be "modern".

Future time must also be thought of in terms of the estimated life of the objects. Objects like buildings and lamp posts grow old and become out-of-date, and the designer must select those materials that are adequate for their life, no more and no less.

Until comparatively recent times the growth of cit­ies has been without purpose in any sense. Cities must grow, for growth is a law of life. But this natural overgrowth should have aroused action to restore balance. Mere size, as such, is no index of greatness.

All overgrowth means overcrowding, which is loss of space, one of the vital needs of cities. The lesson that has to be learned is that natural growth, and all the other forms of growth have to be made subject to will and intelligence, or the city must be harmed. This is a certain lesson of history.

It is now generally becoming accepted that we need to redress the balance of population between one town and another, and between towns and the countryside. Very large towns should not be allowed to absorb more of the countryside and the groups of town should be prevented from turning into amorphous built-up areas.

 

Внеаудиторное чтение, 3 семестр

Часть 1

Laboratories

There are several laboratories at the building department and the best of them is the laboratory of the Chair of Mechanics of Engineering. It is one of the best equipped laboratories in the institute and the students of almost all the departments have their practical training there.









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