Note: The following texts are for the master students who are ...

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Note:

The following
texts are for the master students
who are preparing for the English state
exam.

The texts will be followed by reading comprehension and vocabulary exercis
es. Also will
be added speaking

and grammar tasks in the exam.



School of Civil Engineering


Text 1


Architectural Space

Architectural space is a powerful shaper of behavior. Winston Churchill understood this well
when, in 1943, before the House of Commons, he said, “We shape our buildings, and afterwar
ds
our buildings shape us.” The chamber in which the Commons had been meeting for nearly a
century had been gutted by a German bomb in 1941, and Parliament was beginning to consider
alternative ways of reconstructing the chamber. When Parliament had first
begun to meet, in the
thirteenth century, it had been given the use of rooms in medieval Westminster Palace and had
moved into the palace chapel. A typical Gothic chapel, it was narrow and tall, with parallel rows
of choir stalls on either side of the aisl
e down the center. The members of Parliament sat in the
stalls, dividing themselves into two groups, one the government in power and the other the loyal
opposition. Seldom did members take the brave step of crossing the aisle to change political
allegiance
. When the House of Parliament had to be rebuilt after a fire in 1834, the Gothic form
was followed, and Churchill argued that this ought to be done again in 1943. There were those
who advocated rebuilding the House with a fan of seats in a board semicircl
e, as used in
legislative chambers in the United States and France. But Churchill convincingly argued that the
form of English parliamentary government had been shaped by the physical environment in
which it had first been housed; to change that environmen
t, to give it a different behavioral
space, would change the very nature of parliamentary operation. The English had first shaped
their architecture, and then that architecture had shaped English government and history.
Through Churchill’s persuasion, the
Houses of Parliament were rebuilt with the medieval
arrangement of facing rows of parallel seats looking across a central aisle.


Text 2

Mathematical Systems

Mathematical systems of proportion originate from the Pythagorean concept of ‘all is number’
and t
he belief that certain numerical relationships manifest the harmonic structure of the
universe. One of these relationships that has been in use ever since the days of antiquity is the
proportion known as the Golden Section. The Greeks recognized the domina
ting role the Golden
Section played in the proportions of the human body. Believing that both humanity and the
shrines housing their deities should belong to a higher universal order, they utilized these same
proportions in their temple structures. Renaiss
ance architects also explored the Golden Section in
their work. In more recent times, Le Corbusier based his Modulor system on the Golden Section.
Its use in architecture endures even today. The Golden Section can be defined as the radio
between two sectio
ns of a line, or the two dimensions of a plane figure, in which the lesser of the
two is to the greater is to the sum of both. It can be expressed algebraically by the equation of
two ratios: a/b=b/(a+b).










The
Golden Section has some remarkab
le algebraic and geometric properties that account for its
existence in architecture as well as the structures of many living organisms. Any progression
based on the Golden Section is at once additive and geometrical.







Another
progression that closely approximates the Golden Section in whole numbers is the
Fibonacci Series: 1,1,2,3,5,8,13… Each term again is the sum of the two preceding ones, and the
radio between two consecutive terms tends to approximate the Golden Section as
the series
progresses to infinity.

Text 3

Rhythm

There are many types of rhythm which are of special importance in building. First, there is the
repetition of shapes
-
windows, doors, columns, wall areas, and so on. Second, there is the
repetition of dimensi
ons, such as the dimensions between supports or those of bay spacing. In the
first case
-
the repetition of shapes
-

the spacing can vary without destroying the rhythmical
character. Conversely, where dimensions are equal, the units may vary in size or shape
and
rhythm will still remain. It is this rhythmical quality of dimension repetition which accounts for
much of the beauty of well
-
designed lettering


a quality that is especially marked in carved
inscriptions.










A third and
more complex ty
pe of rhythm is based on the repetition of differences. Thus, if we have of lines,
parallel to each other, in which the distance between the second pair is greatest that between the
first pair and the distance between the third pair greater than that betwe
en the second pair, we
inevitably establish an irregular, progressive rhythm. And so with lines of varying length, placed
continuously: we may start from a dot, have a dash, then one longer still; the effect will be
definitely rhythmical and will, moreover
, imply a strong sense of motion, either from the small to
the large or from the large to the small. We can even combine ascending and descending
progressions in the same rhythmical series, building up from small to large and then gradually
returning to sm
all again, or, conversely, working from large to small to large. In the latter case,
however, the relationship may be felt as constricted. More useful is the combination in which the
large is in the center, with a sense of swelling to an important element
and diminishing to a small
one
-

progressing from a quiet beginning to a climax and then relaxing again.


Text 4

Highway

Highway engineering is both an art and a science. A well
-
designed highway should possess
internal harmony
-
motorists should be able to s
ee smooth lines ahead and have a clear vision of
the landscape at the sides. The highway also should have external harmony
-
to the eye of an
onlooker, the highway should fit in well with its surroundings. These requirements demand
something akin to the visi
on and imagination of an artist, one who can visualize the three
-
dimensional aspects of the various combinations of horizontal and vertical curves, of cuts
merging smoothly with fills, of side slopes blending with the terrain.







The highway, ho
wever, is primarily a transportation medium. It should be built to
endure and to provide adequately foe safe passage of vehicles. To achieve this objective, the
design must adopt certain criteria for strength, safety, and uniformity. Most of these criteria

have
been developed over many years in the hard school of experience; some have evolved through
research and testing. Thus, certain standard formulas have been established. But these always are
subject to modifications since roads are intimately associate
d with the earth’s surface, which
seldom conforms to mathematical concepts.


Text 5

Skyscrapers

People started building skyscrapers not only because of new technological of new technological
discoveries, but also because they are needed to effectively utilize expensive land and have
office workers close to each other. The steel frame developed with s
everal buildings in New
York and Chicago advancing the technology, which allowed the steel frame to carry a building
on its own. Suddenly, it was possible to live and work in colossal towers, hundreds of feet above
the ground. People didn’t construct many
buildings made of bricks and mortar more than 10
stories tall until the late 1800s. The main technological advancement that made skyscrapers
possible was the development of mass iron and steel production. Skyscrapers were then erected
in the growing Americ
an metropolitan centers, most notably Chicago. Steel, which is even
lighter and stronger than iron, made it possible to build even taller buildings. Many skyscrapers
are built almost entirely of steel and glass, giving the occupants a spectacular view of t
heir city.








The skyscraper race is far from over.
There are more than 5 proposed buildings that would break the current record. According to
some engineering experts, the real limitation is money, not technology.







Experts are div
ided about how high we can really go in the near future. Some say
we could build a mile
-
high (5,280 ft, or 1,609m) building with existing technology, while others
say we would need to develop lighter, stronger materials, faster elevators and advanced sway
dampers before these buildings were feasible. Speaking only hypothetically, most engineers will
not impose an upper limit. Future technology advances could lead to sky
-
high cities, many
experts say, housing a million people or more.


Text 6

Characteristics

of Concrete

Portland cement concrete is a simple material in appearance with a very complex internal nature.
In contrast to its internal complexity, concrete’s versatility, durability, and economy have made it
the world’s most used construction material.
This can be seen in the variety of structures it is
used in, from highways, bridges, buildings, and dams to floors, sidewalks, and even works of art.
The use of concrete is unlimited and not even earthbound, as indicated by recent interest.
As wit
h most rocklike substances, concrete has a high compressive strength and a very low
tensile strength. Reinforced concrete is a combination of concrete and steel wherein the steel
reinforcement provides the tensile strength lacking in the concrete.












Concrete is strong in compression, but weak in
tension: its tensile strength varies from 8 to 14 percent of its compressive strength. Due to such a
low tensile capacity, flexural cracks develop at early stages of loading. In order to reduce or
preve
nt such cracks from developing, a concentric force is imposed in the longitudinal direction
of the structural elements. This force prevents the cracks from developing by eliminating or
considerably reducing the tensile stresses at the critical mid
-
span and

support sections at service
load, thereby raising the bending, shear, and torsional capacities of the sections.


Text 7

Moment

The moment at various points in a structure necessary for plotting a bending moment diagram
may be obtained algebraically by t
aking moments at those points, but the procedure is quite
tedious of there are more than two or three loads applied to the structure.











The change in moment between those points
on a structure has been shown to equal the shear between tho
se points times the distance between
them therefore the change in moment equals the area of the shear diagram between the points.



The relationship between shear and moment greatly simplifies the drawing of moment
diagrams. To determine the moment at a
particular section, it is only necessary to compute the
total area beneath the shear curve, either to the left or to the right of the section, taking into
account the algebraic signs of the various segments of the shear curve. Shear and moment
diagrams are

self
-
checking. If they are initiated at one end of a structure, usually the left, and
check out to the proper value on the other end, the work is probably correct.


Text 8

Deep B
eams

Deep beams are structural elements loaded as beams but having a large d
epth/thickness ratio and
a shear span/depth ratio not exceeding 2 to 2.5, where the shear span in the clear span of the
beam for distributed load. Floor slabs under horizontal loads, wall slabs under vertical loads,
short
-
span beams carrying heavy loads, a
nd some shear walls are examples of this type of
structural elements.



Because of the geometry of deep beams, they behave as two
-
dimensional rather than one
-
dimensional members and subjected to a two
-
dimensional state of
stress. As a result, plane secti
ons before bending do not necessarily remain plane after bending.
The resulting strain distribution is no longer considered linear, and shear deformations that are
neglected in normal beams become significant compared to pure flexure. Consequently, the
str
ess block becomes nonlinear even at the elastic stage. At the limit state of ultimate load, the
compressive stress distribution in the concrete would no longer follow the same parabolic shape
or in tensity as that shown in figure for a normal beam.


Text
9

Sewer

Sewers are classified into three categories: sanitary, storm, and combined. Sanitary sewers are
designed to carry municipal wastewater from homes and commercial establishments. With
proper pretreatment, industrial wastes may also be discharged into

these sewers. Storm sewers
are designed to handle excess rainwater to prevent flooding of low areas. While sanitary sewers
convey wastewater to treatment facilities, storm sewers generally discharge into rivers and
streams. Combined sewers are expected to

accommodate both municipal wastewater and
stormwater. These systems are designed so that during dry periods the wastewater carried to a
treatment facility. During rain storms, the excess water is discharged directly into a river,
stream, or lake without
treatment. Modern design practice discourages the building of combined
sewers, and the continued improvement of our natural water bodies will probably require
extensive replacement of combined sewers with separate systems for sanitary and storm flow.


Tex
t 10

Urban Drainage

When an area is urbanized, trees and vegetation are removed, the drainage pattern is altered,
conveyance is accelerated, and the imperviousness of the area is increased because of the
construction of residential or commercial structures

and roads. Increased imperviousness
decreases infiltration with a consequent increase in the volume of runoff. Improvements in a
drainage system cause runoff to leave the urbanized area faster than a from a similar
undeveloped area. Consequently, the time

for runoff to reach its peak is shorter for an urban
watershed than for an undeveloped watershed. The peak runoff from urbanized watersheds, on
the other hand, is larger than from similar undeveloped watersheds.





Urban stormwater drainage collection
and conveyance systems are designed to remove runoff
from urbanized areas so that flooding is avoided and transportation is not adversely affected. The
cost of this and similar systems is directly dependent on the recurrence interval of rainfall used in
th
e design. Rainfall with5 to 10 years recurrence intervals is most often used in the sizing and
design of the urban drainage system.