3. Introduction
• The caves were the early abodes of man.
• The first hut with bamboo and leaves may be the first civil
engineering construction carried out to satisfy the man’s need
for a shelter.
• Man has been molding his environment throughout the ages for
more comfortable living. In this process various building
structures have comeup.
14. Egyptians constructed huge pyramids.
An image of the Sphinx and a pyramid in Giza in Cairo, Egypt.
Source: https://www.architecturaldigest.com/story/facts-never-knew-
about-pyramids-of-giza
15. The Greeks developed a style of proportions of building
elements; these proportions are known as “The Order of
Architecture”.
Temple of Olympian Zeus, AthensSource: https://www.ancienthistorylists.com/greek-
history/top-10-magnificent-ancient-greek-
architecture/
16. Romans developed arches for vaults and domes.
Colosseum in Rome, Italy
Source: https://blogs.lt.vt.edu/ktwest/2016/02/03/ancient-
roman-architecture/
17. • The period from 1750 A.D. onwards is known as ‘the period of
modern architecture’.
• Due to industrial development, many new methods and
materials of construction were developed.
18. GENERAL
Man requires different types of buildings for his activities:
• Houses, bungalows and flats for his living,
• Hospitals and health centres for his health,
• Schools, colleges and universities for his education,
• Banks, shops, offices, buildings and factories for doing work,
• Railway buildings, bus stations and air terminals for transportation,
• Clubs, theatres and cinema houses for recreation, and temples,
• Mosques, churches, dharmshalas, etc., For worship.
19. The building design has traditionally been the responsibility of the
architect, though the building construction has been the
responsibility of the civil engineer. Also, the structural designs of the
building are the responsibility of a civil engineer. On small projects, a
civil engineer may sometimes be entrusted with the architectural
design work, along with structural designs. The main considerations
in architectural design of buildings for all purposes are as follows:
1. Climate and its effect,
2. People and their requirements,
3. Materials for construction and method of construction, and
4. Regulations and bye-laws of sanctioning authority.
20. Building materials
There are certain general factors which affect the choice of materials
for a particular scheme. Perhaps the most important of these is the
climatic background.
Obviously, different materials and forms of construction have
developed in different parts of the world as a result of climatic
differences.
Another factor is the economic aspect of the choice of materials. The
rapid advance of constructional methods, the increasing
introduction of mechanical tools and plants, and changes in the
organization of the building industry may appreciably influence the
choice of materials.
21. Based on the physical and mechanical properties building materials
used are
1. Bricks: One of the oldest building material brick continues to be a most
popular and leading construction material because of being cheap, durable
and easy to handle and work with. Clay bricks are used for building-up
exterior and interior walls, partitions, piers, footings and other load bearing
structures.
A brick is rectangular in shape and of size that can be conveniently handled
with one hand. Brick may be made of burnt clay or mixture of sand and
lime or of Portland cement concrete. Clay bricks are commonly used since
these are economical and easily available.
The length, width and height of a brick are interrelated as below:
Length of brick = 2 × width of brick + thickness of mortar.
Height of brick = width of brick.
Size of a standard brick (also known as modular brick) should be 19 × 9 × 9
cm and 19 × 9 × 4 cm. When placed in masonry the 19 × 9 × 9 cm brick with
mortar becomes 20 × 10 × 10 cm.
22. An indent called frog, 1–2 cm deep, as shown in Fig., is provided for 9
cm high bricks. The size of frog should be 10 × 4 × 1 cm. The purpose
of providing frog is to form a key for holding the mortar and
therefore, the bricks are laid with frogs on top. Frog is not provided in
4 cm high bricks and extruded bricks. Clay bricks are classified as first
class, second class, third class and fourth class based on their physical
and mechanical properties.
23. 2. Stone: Stone has been defined as the natural, hard substance
formed from minerals and earth material which are present in
rocks. Rock may be defined as the portion of the earth’s crust
having no definite shape and structure. Almost all rocks have a
definite chemical composition and are made up of minerals and
organic matter. Some of the rock-forming minerals are quartz,
felspar, mica, dolomite, etc.
The various types of rocks from which building stones are usually
derived are granite, basalt, trap, marble, slate, sandstone and
limestone.
24. Use of stone in building construction is traditional in the places
where it is produced, although even there its high cost imposes
limitations on its use. The conditions which govern the selection of
stone for structural purposes are cost, fashion, ornamental value and
durability.
As building material stone has gradually lost importance with the
advent of cement and steel. Secondly, the strength of the structural
elements built with stones cannot be rationally analyzed. Other
major factors in overshadowing its use are the difficulties in its
transportation and dressing which consume a lot of time resulting in
slow pace of construction.
25. 3. Wood: Wood is a hard and fibrous substance which forms a major part
of the trunk and branches of a tree. It can also be defined as a natural
polymeric material which practically does not age.
Wood as a building material falls in two major classes—natural and man-
made. With the advances in science and technology, wood in its natural
form as timber, lumber, etc. is being rapidly replaced by composite
wood materials in which natural wood is just a basic ingredient of a
matrix or a laminate.
The latter are found to be more useful and adaptable as they may be
treated chemically, thermally or otherwise as per requirements. Some
examples are plywood, fibreboards, chipboards, compressed wood,
impregnated wood, etc.
26. Wood has many advantages due to which it is preferred over many other
building materials. It is easily available in some cases and easy to transport
and handle, has more thermal insulation, sound absorption and electrical
resistance as compared to steel and concrete.
It is the ideal material to be used in sea water. Wood is a good absorber of
shocks and so is suitable for construction work in hilly areas which are
more prone to earthquakes.
Finally, since wood can be easily worked, repairs and alterations to wood
work can also be done easily. Owing to the above mentioned advantages,
wood is very widely used in buildings as doors, windows, frames,
temporary partition walls, etc. and in roof trusses and ceilings apart from
formwork.
27. 4. Cement: In 1845, Issac C. Johnson invented the cement by increasing
the temperature at which the mixture of limestone and clay were
burned to form clinker. This cement was the prototype of the modern
Portland cement. From then onwards, a gradual improvement in the
properties and qualities of cement has been made possible by
researchers in U.S.A., U.K., France and Germany.
Cements in a general sense are adhesive and cohesive materials
which are capable of bonding together particles of solid matter into a
compact durable mass.
28. It is a cementing material resembling a natural stone quarried from
Portland in U.K. Portland cement may be defined as a product
obtained by finely grinding clinker produced by calcining to initial
fusion.
The ordinary Portland cement has been classified as 33 Grade
(IS269:1989), 43 Grade (IS 8112:1989), and 53 Grade (IS 12669-1987).
These grades resembles the fineness they possess. 33 grade is less
finer and 53 grade is more finer.
29. 5. Aggregates: Aggregates are the materials basically used as filler with
binding material in the production of mortar and concrete.
They are derived from igneous, sedimentary and metamorphic rocks or
manufactured from blast furnace slag, etc. Aggregates form the body of the
concrete, reduce the shrinkage and effect economy.
They occupy 70-80 per cent of the volume and have considerable
influence on the properties of the concrete. It is therefore significantly
important to obtain right type and quality of aggregates at site.
They should be clean, hard, strong, durable and graded in size to achieve
utmost economy from the paste.
To increase the bulk density of concrete, aggregates are used in two
markedly different sizes—the bigger ones known to be coarse aggregate
(grit) and the smaller ones fine aggregate (sand).
The coarse aggregate form the main matrix of concrete and the fine
aggregate from the filler matrix between the coarse aggregate
30. 6. Coarse aggregate: Aggregate retained on 4.75 mm sieve are
identified as coarse. They are obtained by natural disintegration or by
artificial crushing of rocks. The maximum size of aggregate can be 80
mm. The size is governed by the thickness of section, spacing of
reinforcement, clear cover, mixing, handling and placing methods.
These may be uncrushed, crushed or partially crushed gravel or stone
most of which is retained on 4.75 mm IS sieve. They should be hard,
strong, dense, durable, clear and free from deposit and adherent
coatings; and free from injurious amounts of disintegrated pieces,
alkali, organic matter and other deleterious substances. Flaky and
elongated aggregate should be avoided.
31. 7. Fine Aggregate: Aggregate passing through 4.75 mm sieve are
defined as fine. They may be natural sand—deposited by rivers,
crushed stone sand—obtained by crushing stones and crushed gravel
sand. The smallest size of fine aggregate (sand) is 0.06 mm.
Depending upon the particle size, fine aggregates are described as
fine, medium and coarse sands. On the basis of particle size
distribution, the fine aggregates are classed into four zones; the
grading zones being progressively finer from grading zone I to grading
zone IV (IS: 383).
32. Sand (> 0.07 mm) is used as a fine aggregate in mortar and concrete.
It is a granular form of silica. Sand used for mix design is known as
standard sand (IS: 650). In India Ennore Sand is standard sand and in
U.K. it is Leighton-Burrard Sand.
The standard sand should be obtained from Ennore, Tamil Nadu. It
should be quartz, light grey or whitish variety and should be free from
silt. It should (100%) pass through 2-mm IS sieve and should be
(100%) retained on 90- micron IS sieve.
Sand used in mortars for construction purposes should posses at least
85 per cent of the strength of standard sand mortars of like
proportions and consistency.
33. Other building materials include:
1. Cast Iron
2. Reinforcing Steel Bars
3. Aluminium
4. Ceramic
5. Paints
6. Asphalt etc
34. What is a building?
National Building Code of India (SP: 7-2005) defines the building as
‘any structure for Whatsoever purpose and of whatsoever materials
constructed and every part thereof whether used as human
habitation or not and includes foundations, plinth, walls, floors, roofs,
chimneys, plumbing and building services, fixed platforms, verandah,
balcony cornice or projection, part of a building or any thing affixed
thereto or any wall enclosing or intended to enclose any land or space
and signs and outdoor display structures’.
Tents and tarpaulin, shelters are not considered as building.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45. Components of a building
A building has two basic parts:
i. Sub-structure or foundations,
ii. Super-structure
46. Sub-structure or foundations
• Substructure or Foundation is the lower portion of the building,
usually located below the ground level, which transmits the loads of
the superstructure to the supporting soil.
• A foundation is therefore that part of the structure which is in direct
contact with the ground to which the loads are transmitted.
47. Super-structure
• Superstructure is that part of the structure which is above ground
level, and which serves the purpose of its intended use.
• A part of the superstructure, located between the ground level and
the floor level is known as plinth.
48. Plinth
• Plinth is therefore defined as the portion of the structure between
the surface of the surrounding ground and surface of the floor,
immediately above the ground.
• The level of the floor is usually known as the plinth level.
• The built-up covered area measured at the floor level is known as
plinth area.
51. A building has the following components:
• Foundations
• Floor structures
• Masonry units: walls and columns
• Roof structures
• Doors, windows and other openings
• Vertical transportation structures, such as stairs, lifts, ramps etc.
• Building finishes
52. Foundations
The basic function of a foundation is to transmit the dead loads, live
loads and other loads to the subsoil on which it rests in such a way
that
(a) Settlements are within permissible limits, without causing cracks in the
superstructure and
(b) Soil does not fail in shear.
Since it remains below the ground level, the signs of failure of
foundations are not noticeable till it has already affected the
building. It should therefore be designed very carefully.
53. Types of foundation
Foundations may be broadly classified into two heads:
1. Shallow Foundations
2. Deep Foundations
A foundation is shallow if its depth is equal to or less than its width.
In case of deep foundations, the depth is equal to or greater than
its width.
54. Shallow foundations
Shallow foundations may be of following types:
1. Spread footings: Footings which spread the superimposed load of a
wall or column over a larger area are called Spread footings.
56. 2. Combined Footings: A spread footing which supports two or more
columns is termed as combined footing. It may be of rectangular
combined footing, trapezoidal combined footing or combined column
wall footing.
58. 3. Strap Footings: If the independent footings of two columns are
connected by a beam, it is called a strap footing. This type of footing
may be used where the distance between the columns is so more
that a combined trapezoidal footing becomes narrow with high
bending moments.
59. 4. Mat foundation (Raft foundation): A raft or mat is a combined
footing that covers the entire area beneath a structure and supports
all the walls and columns. When the allowable soil pressure is low, or
the building loads are heavy, the use of spread footings would cover
more than one half the area and it may prove economical to use mat
or raft foundation.
Column and footing c/s
60. Deep foundations
Deep foundations may be of the following types:
1. Pile foundation = Here loads are taken to a low level by means of vertical
members which may be of timber, concrete or steel. These may be
adopted when
a. No firm bearing strata exists at any reasonable depth and also loading is uneven.
b. When firm bearing strata exist at a greater depth
c. When pumping of subsoil water would be too costly.
2. Well foundation or caissons= These are box like structure- circular or
rectangular which are sunk from the surface of either land or water to
the desired depth. These have large diameter and used for major
foundation works such as bridges etc
91. • Plastering
• Pointing
• Painting
• Varnishing and polishing
• White washing
• Distempering
• Colour washing or colouring
BUILDING FINISHES
92. BUILDING FINISHES
Building finishes basically perform two functions as pointed
below.
• They give a protective coating to the surfaces which protects
them from weather effects such as rain water, frost, heat etc,
and
• They provide decorative effects which add to the appearance of
the surfaces and building as a whole.
93. 1. PLASTERING
• This is the process of covering various surfaces of the structure with a
plastic material such as cement mortar, lime mortar or composite mortar,
etc to obtain an even, smooth, regular, clean and durable surface.
• Plastering conceals inferior quality materials and defective workmanship
and also provides a protective coating against atmospheric effects. It
further provides a base for receiving other decorative finishes such as
painting, white washing, etc.
94.
95. 2. POINTING
• This is the process of finishing of mortar joints in exposed brick or stone
masonry, which is achieved through two operations.
• Firstly, masonry joints in brick or stone are raked out to a depth of about 15
mm and then these spaces are filled up by a suitable mortar of richer mix.
• Pointing gives a good appearance to the masonry work and also prevents
the entry of water into the wall.
96.
97. 3. PAINTING
• This is the process of coating with paint as a final finish to all surfaces
such as walls, ceilings, wood work, metal work, etc in order to protect them
from weathering effects to prevent decay of wood and corrosion in metal,
and over and above to obtain a clean, colorful and pleasing surface.
98.
99. 4. VARNISHING
• This is the process of applying varnish to the wooden surfaces and also to
the painted surfaces, in order to improve their appearance and protect
them from atmospheric actions.
100.
101. 5. DIS-TEMPERING
• This is the process of applying distemper over the plastered surfaces more
easily and with lesser cost than paints and varnishes, to safeguard them
against weather effects and improve their appearance.
• A distemper as water paint, consist of whiting (i.e. powered chalk), glue or
casein which act as a binder, and suitable proportions of fast colour
pigments.
• Distempers are readily available in a variety of different shades in the form
of a stiff paste or dry powder in sealed tins.
102.
103. 6. WHITE WASHING
• In this process, a mixture of pure fat slaked lime in sufficient quantity of
water is first prepared.
• It is then screened through coarse cloth and a mixture of boiled gum with
rice in certain proportions is added to it.
• The solution so formed, called white-wash, is then applied by brushes to a
specified number of coats, usually three.
104.
105. 7. COLOUR WASHING
• It is similar to white washing except a coloring pigment of desired shade
and nature, unaffected by lime, is added to white wash.
• Colour washing is applied in one or two coats only.
109. Dead load
• Dead loads, also known as permanent or static loads, are those that
remain relatively constant over time and comprise, for example, the weight
of a building’s structural elements, such as beams, walls, roof and
structural flooring components.
• Dead loads may also include permanent non-structural partitions,
immovable fixtures and even built-in cupboards.
• The calculation of dead loads of each structure is calculated by the volume
of each section and multiplied by the unit material weight.
110. Live load
• Live load is a civil engineering term that refers to a load that can change
over time.
• The weight of the load is variable or shifts locations, such as when people
are walking around in a building.
• A live load can be expressed either as a uniformly distributed load (UDL)
or as one acting on a concentrated area (point load).
111. Wind load
• Wind loads can be applied by the movement of air relative to a structure,
and analysis draws upon an understanding of meteorology and
aerodynamics as well as structures.
• Wind load may not be a significant concern for small, massive, low-level
buildings, but it gains importance with height, the use of lighter materials
and the use of shapes that may affect the flow of air, typically roof forms.
• Where the dead weight of a structure is insufficient to resist wind loads,
additional structure and fixings may be required.
• Wind load is required to be considered in structural design especially when
the height of the building exceeds two times the dimensions transverse to
the exposed wind surface.
112. Snow load
• This is the load that can be imposed by the accumulation of snow and is
more of a concern in geographic regions where snowfalls can be heavy
and frequent.
• Significant quantities of snow can accumulate, adding a sizable load to a
structure.
• The shape of a roof is a particularly important factor in the magnitude of
the snow load.
113. Earthquake load
• Earthquake load takes place due to the inertia force produced in the
building because of seismic excitations. Inertia force varies with the mass.
The higher mass of the structure will imply that the earthquake loading will
also be high.
• When the earthquake load exceeds the moment of resistance offered by
the element, then the structure will break or damage.
• Buildings in areas of seismic activity need to be carefully analysed and
designed to ensure they do not fail if an earthquake should occur.
