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BUILDING MATERIAL
A
MINOR PROJECT REPORT
Submitted in partial fulfilment of the requirement for the award of Degree of
BACHELOR OF ENGINEERING
IN
CIVIL ENGINEERING
Submitted to
Rajiv Gandhi Proudyogiki Vishwavidyalaya BHOPAL (M.P.)
Submitted By
SACHIN GUPTA (0127CE111044)
Under the supervision of
Mr. Khelendra
Assistant Professor, Department of
Civil Engineering
BANSAL COLLEGE OF ENGINEERING MANDIDEEP, BHOPAL
BATCH 2011-15 BANSAL COLLEGE OF ENGINEERINGMANDIDEEP, BHOPAL
Department of Civil Engineering
CERTIFICATE
This is to certify that Sachin Gupta (0127CE111044), student of B.E. Final year 7th semester
(Civil engineering) has completed Minor Project entitled “THE BUILDING MATERIAL”
during the academic session 2014-15 under my guidance & supervision. I approve the
project for submission as required for partial fulfillment for completion of engineering
degree in “Civil Engineering”.
Guided & Approved by:
Mr. Khelendra
Assistant Professor, Department of
Civil Engineering
Forwarded by:
A.K.Varshney Dr. S.C. Soni
PROFESSOR & HOD DIRECTOR
(DEPTT OF CE) BCE, MANDIDEEP BCE, MANDIDEEP
ACKNOWLEDGEMENT
I express my sincere thanks to Prof. Mr. Khelendra (Assistant
Professor, Dept. of Civil Engineering), my project in charge, who
guided me through the project also gave valuable suggestions and
guidance for completing the project. He helped me to understand the
intricate issues involved in project-making besides effectively
presenting it. These intricacies would have been lost otherwise. My
project has been a success only because of his guidance.
We are highly grateful to Prof. A.K.Varshney (HOD, Dept. Of
Civil Engineering) and Dr. S.C. Soni (Director, Bansal
College Of Engineering, Mandideep) for providing us their
valuable, suggestions, motivation & ideas during whole project work.
We are also thankful to the whole civil department for providing us the
technical support to carry out the project work, to let us utilize all the
necessary facilities of the institute and guidance at each & every step
during the project work.
INTRODUCTION Building material is any material which is used for construction purposes.
Many naturally occurring substances, such as clay, rocks, sand, and wood, even twigs
and leaves, have been used to construct buildings. Apart from naturally occurring
materials, many man-made products are in use, some more and some less synthetic.
The manufacture of building materials is an established industry in many countries
and the use of these materials is typically segmented into specific specialty trades,
such as carpentry, insulation, plumbing, and roofing work. They provide the make-up
of habitats and structures including homes.
Naturally occurring substances
Brush
Ice and snow
Mud and clay
Wet-laid clay walls
Structural clay blocks and bricks
Sand
Stone or rock
Thatch
Wood and timber
Man-made substances
Fired bricks and clay blocks
Cement
Concrete
Fabric
Foam
Glass
Gypcrete
Metal
Plastics
Papers and membranes
Ceramics
Naturally occurring substances
Brush
Brush structures are built entirely from plant parts and were used in primitive cultures such as Native
Americans, pygmy peoples in Africa These are built mostly with branches, twigs and leaves, and bark, similar to a beaver's lodge. These were variously named wikiups, lean-tos, and so forth.
An extension on the brush building idea is the wattle and daub process in which clay soils or dung,
usually cow, are used to fill in and cover a woven brush structure. This gives the structure more thermal mass and strength. Wattle and daub is one of the oldest building techniques. Many older timber frame
buildings incorporate wattle and daub as non load bearing walls between the timber frames.
( View of a group of Mohaves in a brush hut)
Ice and snow Snow and occasionally ice were used by the Inuit peoples for igloos and snow is used to built a shelter called a quinzhee. Ice has also been used for ice hotels as a tourist attraction in northern climates
Mud and clay Clay based buildings usually come in two distinct types. One being when the walls are made directly with the mud mixture, and the other being walls built by stacking air-dried building blocks called mud bricks.
Other uses of clay in building is combined with straws to create light clay, wattle and daub, and mud
plaster.
Wet-laid clay walls
Wet-laid, or damp, walls are made by using the mud or clay mixture directly without forming blocks and drying them first. The amount of and type of each material in the mixture used leads to different styles of
buildings. The deciding factor is usually connected with the quality of the soil being used.
Structural clay blocks and bricks
Mud-bricks, also known by their Spanish name adobe are ancient building materials with evidence dating back thousands of years BC. Compressed earth blocks are a more modern type of brick used for building more frequently in industrialized society since the building blocks can be manufactured off site in a
centralized location at a brickworks and transported to multiple building locations. These blocks can also be monetized more easily and sold.
Structural mud bricks are almost always made using clay, often clay soil and a binder are the only
ingredients used, but other ingredients can include sand, lime, concrete, stone and other binders. The formed or compressed block is then air dried and can be laid dry or with a mortar or clay slip.
`
Sand Sand is used with cement, and sometimes lime, to make mortar for masonry work and plaster. Sand is also used as a part of the concrete mix. An important low-cost building material in countries with high sand content soils is the Sandcrete block, which is weaker but cheaper than fired clay bricks.
Stone or rock Rock structures have existed for as long as history can recall. It is the longest lasting building material
available, and is usually readily available. There are many types of rock throughout the world, all with differing attributes that make them better or worse for particular uses. Rock is a very dense material so it gives a lot of protection too; its main drawback as a material is its weight and awkwardness. Its energy
density is also considered a big drawback, as stone is hard to keep warm without using large amounts of heating resources.
Dry-stone walls have been built for as long as humans have put one stone on top of another. Eventually,
different forms of mortar were used to hold the stones together, cement being the most commonplace now.
The granite-strewn uplands of Dartmoor National Park, United Kingdom, for example, provided ample resources for early settlers. Circular huts were constructed from loose granite rocks throughout the Neolithic and early Bronze Age, and the remains of an estimated 5,000 can still be seen today. Granite continued to be
used throughout the Medieval period (see Dartmoor longhouse) and into modern times. Slate is another stone type, commonly used as roofing material in the United Kingdom and other parts of the world where it
is found.
Stone buildings can be seen in most major cities; some civilizations built entirely with stone such as the Egyptian and Aztec pyramids and the structures of the Inca civilization.
Thatch Thatch is one of the oldest of building materials known; grass is a good insulator and easily harvested. Many African tribes have lived in homes made completely of grasses and sand year-round. In Europe, thatch roofs
on homes were once prevalent but the material fell out of favor as industrialization and improved transport increased the availability of other materials. Today, though, the practice is undergoing a revival. In the
Netherlands, for instance, many new buildings have thatched roofs with special ridge tiles on top.
Wood and timber Wood has been used as a building material for thousands of years in its natural state. Today, engineered
wood is becoming very common in industrialized countries. Wood is a product of trees, and sometimes
other fibrous plants, used for construction purposes when cut or pressed into lumber and timber, such as
boards, planks and similar materials.
2.Man-made substances
Fired bricks and clay blocks Bricks are made in a similar way to mud-bricks except without the fibrous binder such as straw and
are fired ("burned" in a brick clamp or kiln) after they have air-dried to permanently harden them.
Kiln fired clay bricks are a ceramic material. Fired bricks can be solid or have hollow cavities to aid in drying and make them lighter and easier to transport. The individual bricks are placed upon each
other in courses using mortar. Successive courses being used to build up walls, arches, and other architectural elements. Fired brick walls are usually substantially thinner than cob/adobe while
keeping the same vertical strength. They require more energy to create but are easier to transport and store, and are lighter than stone blocks. Romans extensively used fired brick of a shape and
type now called Roman bricks.[11] Building with brick gained much popularity in the mid-18th century and 19th centuries. This was due to lower costs with increases in brick manufacturing and
fire-safety in the ever crowding cities.
The cinder block supplemented or replaced fired bricks in the late 20th century often being used for the inner parts of masonry walls and by themselves.
Structural clay tiles (clay blocks) are clay or terracotta and typically are perforated with holes.
COMPOSITION OF BRICKS
Bricks generally are made of a mixture of clay and sand (to which coal and other foreign
substances are sometimes added), which is subjected to various processes, differing
according to the nature of the material, the method of manufacture and the character of
the finished product.
After being properly prepared the clay is formed in moulds to the desired shape, then dried and burnt.
The Clay. - The quality of a brick depends principally upon the kind of clay used. The material general ly employed for
making common bricks consists of a sandy clay, or silicate of alumina, usually containing small quantities of lime
magnesia and iron oxide.
a)physical properties
Bulk Density : 1915 Kg/m³
Modulus of Rupture : 5 MPa Permanent Linear Change on reheating 5 hrs. @ 1400°C : -0.35%
Cold Compressive Strength : 15 MPa Thermal Conductivity @ 750°C : 1.01 W/m.°K
Apparent Porosity : 28%
b)chemical properties
Alumina : 23%
Silica : 73% Ferric Oxide : 1.4%
Accessory Oxides : 1.1% Titania : 1% Fused Frits (ceramic composition/s)
Test to Justify Brick Quality
o Compressive strength test: This test is done to know the compressive strength of
brick. It is also called crushing strength of brick. Generally 5 specimens of bricks are taken to
laboratory for testing and tested one by one. In this test a brick specimen is put on crushing machine and applied pressure till it breaks. The ultimate pressure at which brick is crushed is taken into account. All five brick specimens are tested one by one and average result is taken as brick’s
compressive/crushing strength.
o Water Absorption test: In this test bricks are weighed in dry condition and let them
immersed in fresh water for 24 hours. After 24 hours of immersion those are taken out from water
and wipe out with cloth. Then brick is weighed in wet condition. The difference between weights is the water absorbed by brick. The percentage of water absorption is then calculated.
The less water absorbed by brick the greater its quality. Good quality brick doesn’t absorb more than 20% water of its own weight.
o Efflorescense test: The presence of alkalies in bricks is harmful and they form a gray or
white layer on brick surface by absorbing moisture. To find out the presence of alkalis in bricks this test is performed. In this test a brick is immersed in fresh water for 24 hours and then it’s taken out
from water and allowed to dry in shade.
If the whitish layer is not visible on surface it proofs that absence of alkalis in brick. If the whitish layer visible about 10% of brick surface then the presence of alkalis is in acceptable range. If that is about 50% of
surface then it is moderate. If the alkalis’s presence is over 50% then the brick is severely affected by alkalies
o Hardness test: In this test a scratch is made on brick surface with a hard thing. If that doesn’t
left any impression on brick then that is good quality brick.
o Size, shape and color test: In this test randomly collected 20 bricks are staked along
lengthwise, widthwise and heightwise and then those are measured to know the variation of sizes as per standard. Bricks are closely viewed to check if its edges are sharp and straight and uniform in
shape. A good quality brick should have bright and uniform color throughout.
o Soundness test: In this test two bricks are held by both hands and struck with one another. If
the bricks give clear metallic ringing sound and don’t break then those are good quality bricks.
o Structure test: In this test a brick is broken or a broken brick is collected and closely
observed. If there are any flows, cracks or holes present on that broken face then that isn’t good quality brick.
CEMENT
A cement is a binder, a substance that sets and hardens and can bind other materials together. The word
"cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling
modern concrete that was made from crushed rock with burnt lime as binder. The volcanic ash and pulverized brick additives that were added to the burnt lime to obtain a hydraulic binder were later
referred to as cementum, cimentum, cäment, and cement.
Cements used in construction can be characterized as being either hydraulic or non-hydraulic, depending upon the ability of the cement to be used in the presence of water
o Non-hydraulic cement will not set in wet conditions or underwater, it sets as the cement dries and reacts with carbon dioxide in the air. It can be attacked by some aggressive chemicals after setting.
o Hydraulic cement is made by replacing some of the cement in a mix with activated aluminium silicates, pozzolanas, such as fly ash. This allows setting in wet condition or underwater and further
protects the hardened material from chemical attack .
The chemical process for hydraulic cement found by ancient Romans used volcanic ash (activated aluminium silicates). Presently cheaper than volcanic ash, fly ash from power stations, recovered as
a pollution control measure, or other waste or by products are used as pozzolanas with plain cement to produce hydraulic cement. Pozzolanas can constitute up to 40% of Portland cement.
Hydraulic cement can harden underwater or when constantly exposed to wet weather. The chemical reaction results in hydrates that are not very water-soluble and so are quite durable in water and safe from chemical attack.
The most important uses of cement are as a component in the production of mortar in masonry,
and of concrete, a combination of cement and an aggregate to form a strong building material.
Non-hydraulic cement, such as slaked lime (calcium hydroxide mixed with water), harden by carbonation
in presence of the carbon dioxide naturally present in the air. First calcium oxide is produced by lime calcination at temperatures above 825 °C (1,517 °F) for about 10 hours at atmospheric pressure:
CaCO3 → CaO + CO2
The calcium oxide is then spent (slaked) mixing it with water to make slaked lime:
CaO + H2O → Ca(OH)2
Once the water in excess from the slaked lime is completely evaporated (this process is technically called
setting), the carbonation starts:
Ca(OH)2 + CO2 → CaCO3 + H2O
This reaction takes a significant amount of time because the partial pressure of carbon dioxide in the air is low. The carbonation reaction requires the dry cement to be exposed to air, for this reason the slaked lime is a non-hydraulic cement and cannot be used under water. This whole process is called the lime cycle.
Conversely, the chemistry ruling the action of the hydraulic cement is hydration. Hydraulic cements (such as
Portland cement) are made of a mixture of silicates and oxides, the four main components being:
Belite (2CaO·SiO2);
Alite (3CaO·SiO2);
Celite (3CaO·Al2O3);
Brownmillerite (4CaO·Al2O3·Fe2O3).
The silicates are responsible of the mechanical properties of the cement, the celite and the browmillerite
are essential to allow the formation of the liquid phase during the kiln sintering (firing). The chemistry of the above listed reactions is not completely clear and is still the object of research.
Cement manufacturing: components of a cement plant
Cement is typically made from limestone and clay or shale. These raw materials are extracted from the quarry crushed to a very fine powder and then blended in the correct proportions.
This blended raw material is called the 'raw feed' or 'kiln feed' and is heated in a rotary kiln where it reaches a temperature of about 1400 C to 1500 C. In its simplest form, the rotary kiln is a tube up to 200 metres long and perhaps 6 metres in diameter, with a long flame at one end. The raw feed enters the kiln at the cool end
and gradually passes down to the hot end, then falls out of the kiln and cools down.
The material formed in the kiln is described as 'clinker' and is typically composed of rounded nodules between 1mm and 25mm across.
After cooling, the clinker may be stored temporarily in a clinker store, or it may pass directly to the cement
mill.
The cement mill grinds the clinker to a fine powder. A small amount of gypsum - a form of calcium sulfate - is normally ground up with the clinker. The gypsum controls the setting properties of the cement when water
is added.
TEST OF CEMENT
Various Lab Test On Cement
FIELD TESTS ON CEMENT
Various Lab Test On Cement
Fineness Soundness Consistency Initial And Final Setting Time Of Cement
FINENESSS
we need to determine the fineness of cement by dry sieving as per IS: 4031 (Part 1) – 1996.The principle of this is that we determine the proportion of cement whose grain size is larger then specified mesh size. The apparatus used are 90µm IS Sieve, Balance capable of weighing 10g to the nearest 10mg, A nylon or pure bristle brush, preferably with 25 to 40mm, bristle, for cleaning the sieve. Sieve shown in pic below is not the actual 90µm seive.Its just for reference.
Procedure to determine fineness of cement
i) Weigh approximately 10g of cement to the nearest 0.01g and place it on the sieve. ii) Agitate the sieve by swirling, planetary and linear movements, until no more fine material passes through it. iii) Weigh the residue and express its mass as a percentage R1,of the quantity first placed on the sieve to the nearest 0.1 percent. iv) Gently brush all the fine material off the base of the sieve. v) Repeat the whole procedure using a fresh 10g sample to obtain R2. Then calculate R as the mean of R1 and R2 as a percentage, expressed to the nearest 0.1 percent. When the results differ by more than 1 percent absolute, carry out a third sieving and calculate the mean of the three values.
SOUNDNESS
Soundness of cement is determined by Le-Chatelier method as per IS: 4031 (Part 3) – 1988. Apparatus – The apparatus for conducting the Le-Chatelier test should conform to IS: 5514 – 1969
Balance, whose permissible variation at a load of 1000g should be +1.0g and Water bath.
Procedure to determine soundness of cement
i) Place the mould on a glass sheet and fill it with the cement paste formed by gauging cement with 0.78 times the water required to give a paste of standard consistency. ii) Cover the mould with another piece of glass sheet, place a small weight on this covering glass sheet and immediately submerge the whole assembly in water at a temperature of 27 ± 2oC and keep it there for 24hrs. iii) Measure the distance separating the indicator points to the nearest 0.5mm (say d1 ). iv) Submerge the mould again in water at the temperature prescribed above. Bring the water to boiling point in 25 to 30 minutes and keep it boiling for 3hrs. v) Remove the mould from the water, allow it to cool and measure the distance between the indicator points (say d2 ). vi) (d2 – d1 ) represents the expansion of cement.
CONSISTENCY
The basic aim is to find out the water content required to produce a cement paste of standard consistency as specified by the IS: 4031 (Part 4) – 1988. The principle is that standard consistency of
cement is that consistency at which the Vicat plunger penetrates to a point 5-7mm from the bottom of Vicat mould.
Apparatus – Vicat apparatus conforming to IS: 5513 – 1976, Balance, whose permissible variation at a load of 1000g should be +1.0g, Gauging trowel conforming to IS: 10086 – 1982.
Procedure to determine consistency of cement
i) Weigh approximately 400g of cement and mix it with a weighed quantity of water. The time of gauging should be between 3 to 5 minutes. ii) Fill the Vicat mould with paste and level it with a trowel. iii) Lower the plunger gently till it touches the cement surface. iv) Release the plunger allowing it to sink into the paste.
v) Note the reading on the gauge. vi) Repeat the above procedure taking fresh samples of cement and different quantities of water until the
reading on the gauge is 5 to 7mm.
INITIAL AND FINAL SETTING TIME
We need to calculate the initial and final setting time as per IS: 4031 (Part 5) – 1988. To do so we need Vicat apparatus conforming to IS: 5513 – 1976, Balance, whose permissible variation at a load
of 1000g should be +1.0g, Gauging trowel conforming to IS: 10086 – 1982.
Procedure to determine initial and final setting time of cement i) Prepare a cement paste by gauging the cement with 0.85 times the water required to give a paste of
standard consistency. ii) Start a stop-watch, the moment water is added to the cement.
iii) Fill the Vicat mould completely with the cement paste gauged as above, the mould resting on a non-porous plate and smooth off the surface of the paste making it level with the top of the mould. The cement block thus prepared in the mould is the test block.
A) Initial Setting time
Place the test block under the rod bearing the needle. Lower the needle gently in order to make contact
with the surface of the cement paste and release quickly, allowing it to penetrate the test block. Repeat
the procedure till the needle fails to pierce the test block to a point 5.0 ± 0.5mm measured from the
bottom of the mould.The time period elapsing between the time, water is added to the cement and the
time, the needle fails to pierce the test block by 5.0 ± 0.5mm measured from the bottom of the mould, is
the initial setting time.
B) Final Setting time
Replace the above needle by the one with an annular attachment. The cement should be considered as
finally set when, upon applying the needle gently to the surface of the test block, the needle makes an
impression therein, while the attachment fails to do so. The period elapsing between the time, water is
added to the cement and the time, the needle makes an impression on the surface of the test block, while
the attachment fails to do so, is the final setting time.
FIELD TESTS ON CEMENT
Field tests on cements are carried to know the quality of cement supplied at site. It gives some idea about cement quality based on colour, touch and feel and other tests.
The following are the field tests on cement:
(a) The colour of the cement should be uniform. It should be grey colour with a light greenish shade.
(b) The cement should be free from any hard lumps. Such lumps are formed by the absorption of moisture
from the atmosphere. Any bag of cement containing such lumps should be rejected.
(c) The cement should feel smooth when touched or rubbed in between fingers. If it is felt rough, it indicates adulteration with sand.
(d) If hand is inserted in a bag of cement or heap of cement, it should feel cool and not warm.
(e) If a small quantity of cement is thrown in a bucket of water, the particles should float for some time before it sink.
(f) A thick paste of cement with water is made on a piece of glass plate and it is kept under water for 24
hours. It should set and not crack.
(g) A block of cement 25 mm ×25 mm and 200 mm long is prepared and it is immersed for 7 days in water. It is then placed on supports 15cm apart and it is loaded with a weight of about 34 kg. The block should not show signs of failure.
(h) The briquettes of a lean mortar (1:6) are made. The size of briquette may be about 75 mm ×25 mm ×12 mm. They are immersed in water for a period of 3 days after drying. If cement is of sound quality such
briquettes will not be broken easily
CONCRETE
Concrete is a composite material composed mainly of water, aggregate, and cement. Often, additives and
reinforcements are included in the mixture to achieve the desired physical properties of the finished
material. When these ingredients are mixed together, they form a fluid mass that is easily molded into
shape. Over time, the cement forms a hard matrix which binds the rest of the ingredients together into a
durable stone-like material with many uses.
"Aggregate" consists of large chunks of material in a concrete mix, generally a coarse gravel or crushed rocks such as limestone, or granite, along with finer materials such as sand.
"Cement", most commonly Portland cement is associated with the general term "concrete." A range of
materials can be used as the cement in concrete. One of the most familiar of these alternative cements is asphalt. Other cementitious materials such as fly ash and slag cement, are sometimes added to Portland
cement and become a part of the binder for the aggregate.
Water is then mixed with this dry composite, which produces a semi-liquid that workers can shape (typically by pouring it into a form). The concrete solidifies and hardens through a chemical process called
hydration. The water reacts with the cement, which bonds the other components together, creating a robust stone-like material.
"Chemical admixtures" are added to achieve varied properties. These ingredients may speed or slow down the rate at which the concrete hardens, and impart many other useful properties including increased tensile strength and water resistance.
"Reinforcements" are often added to concrete. Concrete can be formulated with high compressive
strength, but always has lower tensile strength. For this reason it is usually reinforced with materials that are strong in tension (often steel).
"Mineral admixtures" are becoming more popular in recent decades. The use of recycled materials as
concrete ingredients has been gaining popularity because of increasingly stringent environmental legislation, and the discovery that such materials often have complementary and valuable properties. The
most conspicuous of these are fly ash, a by-product of coal-fired power plants, and silica fume, a byproduct of industrial electric arc furnaces. The use of these materials in concrete reduces the amount of resources
required, as the ash and fume act as a cement replacement. This displaces some cement production, an energetically expensive and environmentally problematic process, while reducing the amount of industrial waste that must be disposed of.
Various Lab Test On Concret
These tests are basically divided into two categories
1. Various Lab Test On Fresh Concrete.
a) Slump Test – Workability
b) Compacting Factor
c) Vee- Bee Test
2. Various Lab Test On Hardened Concrete.
a) Rebound Hammer Test b) Ultrasonic Pulse Velocity Test
1)Various Lab Test On Fresh Concrete.
a) Slump Test – Workability
Slump test is used to determine the workability of fresh concrete. Slump test as per IS: 1199 – 1959 is followed.The apparatus used for doing slump test are Slump cone and Tamping rod.
Procedure to determine workability of fresh concrete by slump test. i) The internal surface of the mould is thoroughly cleaned and applied with a light coat of oil. ii) The mould is placed on a smooth, horizontal, rigid and nonabsorbent surface. iii) The mould is then filled in four layers with freshly mixed concrete, each approximately to one-fourth of the height of the mould. iv) Each layer is tamped 25 times by the rounded end of the tamping rod (strokes are distributed evenly over the cross section). v) After the top layer is rodded, the concrete is struck off the level with a trowel.
vi) The mould is removed from the concrete immediately by raising it slowly in the vertical direction. vii) The difference in level between the height of the mould and that of the highest point of the subsided
concrete is measured. viii) This difference in height in mm is the slump of the concrete
b) COMPACTING FACTOR
Compacting factor of fresh concrete is done to determine the workability of fresh concrete by compacting factor test as per IS: 1199 – 1959. The apparatus used is Compacting factor apparatus.
Procedure to determine workability of fresh concrete by compacting factor
test.
i) The sample of concrete is placed in the upper hopper up to the brim. ii ) The trap-door is opened so that the concrete falls into the lower hopper. iii) The trap-door of the lower hopper is opened and the concrete is allowed to fall into the cylinder. iv) The excess concrete remaining above the top level of the cylinder is then cut off with the help of plane blades. v) The concrete in the cylinder is weighed. This is known as weight of partially compacted concrete. vi) The cylinder is filled with a fresh sample of concrete and vibrated to obtain full co mpaction. The concrete in the cylinder is weighed again. This weight is known as the weight of fully compacted concrete .
Compacting factor = (Weight of partially compacted concrete)/(Weight of fully compacted concrete)
VEE-BEE TEST
To determine the workability of fresh concrete by using a Vee-Bee consistometer as per IS: 1199 – 1959. The apparatus used is Vee-Bee consistometer. Procedure to determine workability of fresh concrete by Vee-Bee consistometer.
i) A conventional slump test is performed, placing the slump cone inside the cylindrical part of the consistometer. ii) The glass disc attached to the swivel arm is turned and placed on the top of the concrete in the pot. iii) The electrical vibrator is switched on and a stop-watch is started, simultaneously. iv) Vibration is continued till the conical shape of the concrete disappears and the concrete assumes a cylindrical shape.
v) When the concrete fully assumes a cylindrical shape, the stop-watch is switched off immediately. The time is noted.The consistency of the concrete should be expressed in VB-degrees, which is equal to the
time in seconds recorded above.
Fabric
The tent is the home of choice among nomadic groups all over the world. Two well -known types include the conical teepee and the circular yurt. The tent has been revived as a major construction technique with
the development of tensile architecture and synthetic fabrics. Modern buildings can be made of flexible material such as fabric membranes, and supported by a system of steel cables, rigid or internal, or by air
pressure.
Foam
Recently, synthetic polystyrene or polyurethane foam has been used in combination with structural
materials, such as concrete. It is lightweight, easily shaped, and an excellent insulator. Foam is usually used as part of a structural insulated panel, wherein the foam is sandwiched between wood or cement or insulating concrete forms.
Glass
Glassmaking is considered an art form as well as an industrial process or material.
Clear windows have been used since the invention of glass to cover small openings in a building. Glass panes provided humans with the ability to both let light into rooms while at the same time keeping inclement weather outside.
Glass is generally made from mixtures of sand and silicates, in a very hot fire stove called a kiln, and is very
brittle. Additives are often included the mixture used to produce glass with shades of colors or various
characteristics (such as bulletproof glass or light emittance).
The use of glass in architectural buildings has become very popular in the modern culture. Glass "curtain walls" can be used to cover the entire facade of a building, or it can be used to span over a wide roof
structure in a "space frame". These uses though require some sort of frame to hold sections of glass together, as glass by itself is too brittle and would require an overly large kiln to be used to span such large
areas by itself.
Glass bricks were invented in the early 20th century.
Gypcrete
Gypcrete is a mixture of gypsum plaster and fibreglass rovings. Although plaster and fibres fiborous plaster
have been used for many years, especially for ceilings, it was not until the early 1990s that serious studies of the strength and qualities of a walling system Rapidwall, using a mixture of gypsum plaster and 300mm
plus fibreglass rovings, were investigated. It was discovered, through testing at the University of Adelaide, that these walls had significant, load bearing, shear and lateral resistance together with earthquake-
resistance, fire-resistance, and thermal properties. With an abundance of gypsum (naturally occurring and by-product chemical FGD and phospho gypsums) available worldwide, gypcrete-based building products,
which are fully recyclable, offer significant environmental benefits.
Metal
Metal is used as structural framework for larger buildings such as skyscrapers, or as an external surface covering. There are many types of metals used for building. Metal figures quite prominently in
prefabricated structures such as the Quonset hut, and can be seen used in most cosmopolitan cities. It requires a great deal of human labor to produce metal, especially in the large amounts needed for the
building industries. Corrosion is metal's prime enemy when it comes to longevity.
Steel is a metal alloy whose major component is iron, and is the usual choice for metal structural
building materials. It is strong, flexible, and if refined well and/or treated lasts a long time.
The lower density and better corrosion resistance of aluminium alloys and tin sometimes overcome their greater cost.
(Copper belfry of St. Laurentius church, Bad Neuenahr-Ahrweiler)
Copper is a valued building material because of its advantageous properties (se e: Copper in architecture). These include corrosion resistance, durability, low thermal movement, light weight, radio frequency shielding, lightning protection, sustainability, recyclability, and a wide range of finishes. Copper is
incorporated into roofing, flashing, gutters, downspouts, domes, spires, vaults, wall cladding, building expansion joints, and indoor design elements.
Other metals used include chrome, gold, silver, and titanium. Titanium can be used for structural purposes, but it is much more expensive than steel. Chrome, gold, and silver are used as decoration, because these materials are expensive and lack structural qualities such as tensile strength or hardness.
Plastics
(Plastic pipes penetrating a concrete floor in a Canadian highrise apartment building)
The term "plastics" covers a range of synthetic or semi-synthetic organic condensation or polymerization
products that can be molded or extruded into objects, films, or fibers. Their name is derived from the fact that in their semi-liquid state they are malleable, or have the property of plasticity. Plastics vary immensely
in heat tolerance, hardness, and resiliency. Combined with this adaptability, the general uniformity of composition and lightness of plastics ensures their use in almost all industrial applications today.
Papers and membranes
Building papers and membranes are used for many reasons in construction. One of the oldest building papers is red rosin paper which was known to be in use before 1850 and was used as an underlayment in
exterior walls, roofs, and floors and for protecting a jobsite during construction. Tar paper was invented late in the 19th century and was used for similar purposes as rosin paper and for gravel roofs. Tar paper
has largely fallen out of use supplanted by asphalt felt paper. Felt paper has been supplanted in some uses by synthetic underlayments, particularly in roofing by synthetic underlayments and siding by housewraps.
There are a wide variety of damp proofing and waterproofing membranes used for roofing, basement
waterproofing, and geomembra.
Ceramic
Ceramic building material, often abbreviated to CBM, is an umbrella term used in archaeology to cover all building materials made from baked clay. It is particularly, but not exclusively, used in relation to Roman
building materials.
It is a useful and necessary term because, especially when initially found in archaeological excavation, it may be difficult to distinguish, for example, fragments of bricks from fragments of roofing or fl ooring tiles. However, ceramic building materials are usually readily distinguishable from fragments of ceramic pottery by their rougher finish.
