Fresh Concrete Ppt

1. Fresh Concrete:
It is the concrete phase from time of mixing to end time of
surface finishing.
Concrete Operations:
They include batching, mixing, transporting, placing,
compacting, surface finishing .
curing of in-placed concrete starts 6-10 hours after casting
(placing) and during first few days of hardening is important.
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2. Properties of fresh state which affect hardened state properties of
concrete:
 The potential strength and durability (the ability to withstand
wear, pressure, or damage) of concrete of a given mix
proportion is dependent on the degree of its compaction.
 The first 48 hours are very important for the performance of the
concrete structure.
• It controls the long-term behavior, which influence the
• f'c - ultimate strength
• Ec - elastic modulus
• Creep - Elastic deformations occurs after the concrete is
subjected to a given load, according to Hooke's Law.
Inelastic deformations increase with time as
the concrete experiences a sustained load. This
inelastic deformation, also known as creep.
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3.  Elasticity and Strength of Concrete
 The elastic properties of material are a measure of their
resistance to deformation under an applied load
 Strength usually refers to the maximum stress that a given
kind of sample can carry.
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4. Consistency
• Slump Test
• Flow Test
• Penetration
Test
Workability
• Compacting
Factor Test
• VeBe Time
Test
Segregation Bleeding
•Bleeding
Water Test
• Bleeding - when cement and water come on the top and aggregate is
settle down is called bleeding this is due to specific gravity of
material and improper placing.
• Segregation - it means separation of ingredients of concrete.
• Honey combing - after removal of formwork from column beam
there is hole Is called honeycombing
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5. 5

6. The ability of freshly mixed concrete or mortar to flow; the
usual measurements are slump for concrete, flow for mortar
or grout, and penetration resistance for neat cement paste.
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7.  Consistency is the aspect of workability related to the flow
characteristics of fresh concrete. It is an indication of the
fluidity or wetness of a mix and is measured by the slump test
 However, it must not be assumed that the wetter the mix the
more workable it is. If a mix is too wet, segregation may occur
with resulting honeycomb, excessive bleeding.
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8.  On the other hand, if a mix is too dry it may be difficult to
place and compact, and segregation may occur because of lack
of cohesiveness and plasticity of the paste.
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9. Consistency
Tests
Slump Test
Ball penetration
test
Flow Test
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10. Definition
A slump test is a method used to determine the consistency of
concrete. The consistency or stiffness, indicates how much water to
be used in the mix. The stiffness of the concrete mix should be
matched to the requirements for the finished product quality
 Slump is a measurement of concrete’s workability, or fluidity.
Specification for Concrete Slump Test Apparatus
IS :7320-1974 (Reaffirmed 2008)
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11.  Apparatus
 Slump cone : frustum of a cone, 300 mm (12 in) of height. The
base is 200 mm (8in) in diameter and it has a smaller opening at
the top of 100 mm
 Scale for measurement,
 Temping rod(steel) 15mm diameter, 60cm length.
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12.  Procedure
 The base is placed on a smooth surface and the container is filled
with concrete in three layers, whose workability is to be tested .
 Each layer is temped 25 times with a standard 16 mm (5/8 in)
diameter steel rod, rounded at the end.
 When the mold is completely filled with concrete, the top surface
is struck off (leveled with mold top opening) by means of
screening and rolling motion of the temping rod.
 The mold must be firmly held against its base during the entire
operation so that it could not move due to the pouring of concrete
and this can be done by means of handles or foot – rests brazed to
the mold.
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13.  Procedure
 Immediately after filling is completed and the concrete is leveled,
the cone is slowly and carefully lifted vertically, an unsupported
concrete will now slump.
 The decrease in the height of the center of the slumped concrete is
called slump.
 The slump is measured by placing the cone just besides the slump
concrete and the temping rod is placed over the cone so that it
should also come over the area of slumped concrete.
 The decrease in height of concrete to that of mould is noted with
scale. (usually measured to the nearest 5 mm (1/4 in).
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14.  Types Of Slump
The slumped concrete takes various shapes, and according
to the profile of slumped concrete, the slump is termed as;
 Collapse Slump
 Shear Slump
 True Slump
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15.  Types of Slump
 Collapse Slump
In a collapse slump the concrete collapses completely.
Collapse slump indicates that concrete mix is too wet and the
mix is regarded as harsh and lean
 Shear Slump
If one-half of the cone slides down an inclined plane, the slump is
said to be a shear slump.
If a shear or collapse slump is achieved, a fresh sample should be
taken and the test is repeated.
Shear slump indicates that the concrete lacks cohesion. It may
undergo segregation and bleeding and thus is undesirable for the
durability of concrete.
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16.  True Slump
True slump refers to general drop of the concrete mass evenly all
around without disintegration
This is the only slump which is used in various tests.
Mixes of stiff(hard) consistence have a Zero slump, so that in the
rather dry range no variation can be detected between mixes of
different workability.
However , in a lean mix with a tendency to harshness, a true
slump can easily change to the shear slump type or even to
collapse, and widely different values of slump can be obtained in
different samples from the same mix; thus, the slump test is
unreliable for lean mixes.
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17.  Uses
 The slump test is used to ensure uniformity for different batches
of similar concrete under field conditions and to ascertain the
effects of plasticizers on their introduction.
 This test is very useful on site as a check on the day-to-day or
hour- to-hour variation in the materials being fed into the mixer.
An increase in slump may mean, for instance, that the moisture
content of aggregate has unexpectedly increases.
 Other cause would be a change in the grading of the aggregate,
such as a deficiency of sand.
 Too high or too low a slump gives immediate warning and
enables the mixer operator to remedy the situation.
 This application of slump test as well as its simplicity, is
responsible for its widespread use.
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18. Degree of
workability
Slump (mm)
Compacting
Factor
Use for which
concrete is suitable
Very low 0 - 25 0.78
Very dry mixes; used in road
making. Roads vibrated by
power operated machines
Low 25 - 50 0.85
Low workability mixes; used
for foundations with light
reinforcement. Roads
vibrated by hand operated
Machines
Medium 50 - 100 0.92
Medium workability mixes;
manually compacted flat
slabs using crushed
aggregates. Normal
reinforced concrete
manually compacted and
heavily reinforced sections
with vibrations
High 100 - 175 0.95
High workability concrete;
for sections with
congested reinforcement.
Not normally suitable for
vibration
>Table : Workability, Slump and Compacting Factor of concrete with 19 or 38 mm (3/4 or 11/2 in) maximum size of aggregate. 18

19. Slump (mm) 0 - 20 20 - 40 40 - 120 120 - 200 200 - 220
Consistenc
y
Dry Stiff Plastic Wet Sloppy
>Table : Relation between Consistency and Slump values
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20. 20

21.  Definition
 The property of fresh concrete which is indicated by the
amount of useful internal work required to fully compact the
concrete without bleeding or segregation in the finished
product.
 Workability is one of the physical parameters of concrete
which affects the strength and durability as well as the cost
of labour and appearance of the finished product.
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22. Concrete workability is the relative ease with which a fresh mix
can be handled, placed, compacted, and finished without
segregation or separation of the individual ingredients. Good
workability is required to produce concrete that is both
economical and high in quality.
Fresh concrete has good workability if it can be formed,
compacted, and finished to its final shape and texture with least
effort and without segregation of the ingredients.
Concrete with poor workability does not flow smoothly into
member.
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23.  Factors affecting workability
 Water content in the concrete mix
 Amount of cement & its Properties
 Aggregate Grading (Size Distribution)
 Nature of Aggregate Particles (Shape, Surface Texture, Porosity
etc.)
 Temperature of the concrete mix
 Humidity of the environment
 Mode of compaction
 Method of placement of concrete
 Method of transmission of concrete
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24.  How To improve the workability of concrete
 increase water/cement ratio
 increase size of aggregate
 use well-rounded and smooth aggregate instead of irregular shape
 increase the mixing time
 use non-porous and saturated aggregate
 with addition of air-entraining mixtures
An on site simple test for determining workability is the SLUMP
TEST.
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25. Introduction
Procedure
Apparatus
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26.  Introduction
 These tests were developed in the UK by Glanville (
1947 ) and it measures the degree of compaction for the
standard amount of work and thus offer a direct and
reasonably reliable assessment(ABILITY) of the
workability Of concrete . the test require measurement
of the weight of the partially and fully compacted
concrete and the ratio the partially compacted weight to
the fully compacted weight, which is always less than
one, is known as compacted factor .
 For the normal range of concrete the compacting factor
lies between 0.8 - 0.92
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27.  Apparatus
 Trowels
 Hand Scoop (15.2 cm long)
 Rod of steel or other suitable material
(1.6 cm diameter, 61 cm long rounded
at one end ).
 Balance.
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28. Workability Slump (mm) C.F Uses
Very Low 0 - 25 0.78 Roads - Pavements
Low 25 - 50 0.85
Foundations
Concrete
Medium 25 - 100 0.92 Reinforced Concrete
High 100 - 175 0.95
Reinforced Concrete
(High Reinforcement)
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29. 29

30. Segregation can be defined as separation of the constituents of a
heterogeneous mixture so that their distribution is no longer
uniform. The differences in the size particles of the concrete
constituents are the primary cause of segregation, but its extent
can be controlled by the choice of suitable grading and by care
handling. Concrete mixes should not segregate (i.e to be
cohesive; the absence of segregation is essential if full
compaction is to be achieved.
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31. There are two forms of segregation:
1- The coarser particles tend to separate out since they travel
further along a slope or settle more than finer particles. It occurs
when the mix is too dry
2- It occurs in wet mixes through separation of cement paste from
the mix.
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32. The actual extent of segregation depends on the method of
handling and placing of concrete. If concrete does not have far
to travel and is transferred directly from the wheelbarrow to the
final position in the formwork, the danger of segregation is small.
On the other hand, dropping concrete from a considerable height,
particularly with changes of direction, and discharging against an
obstacle, all encourage segregation.
Therefore, such circumstances should be under control. With
correct method of handling, transporting, and placing, the
likelihood of segregation can be greatly reduced.
Air entraining admixtures can be used to control segregation.
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33.  Segregation makes the concrete
 Weaker,
 Less durable,
 And will leave a poor surface finish
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34.  Basic types of segregation
 Coarse segregation : Occurs when gradation is shifted to
include too much coarse aggregate and not enough fine
aggregate. Coarse segregation is characterized by low
asphalt content, low density, high air voids, rough
surface texture, and fatigue failure.
 Fine segregation : Occurs when gradation is shifted to
include too much fine aggregate and not enough course
aggregate. High asphalt content, low density, smooth
surface texture.
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35.  To Avoid Segregation
 Check the concrete is not 'too wet' or 'too dry'.
 Make sure the concrete is properly mixed. It is important
that the concrete is mixed at the correct speed in a transit
mixer for at least two minutes immediately prior to
discharge.
 The concrete should be placed as soon as possible.
 When transporting the mix, load carefully.
 Always pour new concrete into the face of concrete already
in place.
 When compacting with a poker vibrator be sure to use it
carefully
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36.  To Avoid Segregation
 If placing concrete straight from a truck, pour vertically and
never let the concrete fall more than one-and-a-half
meters.
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38. 38

39. 39

40. Introduction
Bleeding, known also as water gain, is a form of segregation in which
some of the water in the mix tends to rise to the surface of freshly placed
concrete. This is caused by the inability of the solid constituents of the
mix to hold all of the mixing water when they settle downwards.
Bleeding can be expressed quantitatively as the total settlement
(reduction in height) per unit height of concrete, and the bleeding
capacity as well as the rate of bleeding can be determined experimentally
using the test of ASTM C 232-04. When the cement paste has stiffened
sufficiently, bleeding of concrete ceases.
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41. When there is excessive quantity of water in the mix or due to
excessive compaction. Bleeding causes the formation of pores
and renders the concrete weak.
Bleeding can be avoided by suitably controlling the quantity of
water in the concrete and using finer grading of aggregates.
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42.  Bleeding Process
 Almost all freshly placed concrete bleeds. As aggregate and
cement particles settle, they force excess mixing water
upward. The process continues until settlement stops, either
because of solids bridging or because the concrete has set.
 The total amount of bleeding or settlement depends on mix
properties, primarily water content and amount of fines
(cement, fly ash, fine sand). Increasing water content
increases bleeding, and increasing the amount of fines reduces
bleeding.
 Amount of bleeding is also proportional to the depth of
concrete placed. More bleed water rises in deep sections than
in thin ones.
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43.  Bleeding usually occurs gradually by uniform seepage over
the whole surface, but sometimes vertical channels form.
Water flows fast enough in these channels to carry fine
particles of cement and sand, leaving "wormholes" in the
interior.
 This leads to freezing and thawing damage and rebar
corrosion.
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44. Effects Of Excessive bleeding
 As a result of bleeding, the top of every layer of concrete placed
may become too wet, and, if the water is trapped by
superimposed concrete, a porous and weak layer of non-durable
concrete will result.
 If the bleeding water is remixed during the finishing of the top
surface, a weak wearing surface will be formed. This can be
avoided by delaying the finishing operations until the bleeding
water has evaporated, and also by the use of wood floats and by
avoidance of over-working of the surface.
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45.  On the other hand, if evaporation of water from the surface of
the concrete is faster than the bleeding rate, plastic shrinkage
cracking may result.
 In addition to accumulating at the upper surface of the
concrete, some of the rising water traps on the underside of
large aggregate particles or of reinforcement, thus creating
zones of poor bond. This water leaves behind voids and, since
all these voids are oriented in the same direction, the
permeability of the concrete in a horizontal plane may
increases.
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46.  Although dependent on the water content of the mix, the
tendency to bleeding depends largely on the properties of the
cement. Bleeding is lower with finer cements and is also
affected by certain chemical factors: there is less bleeding
when the cement has a high alkali content, a high C3A
content, or when calcium chloride is added
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47. 47

48.  The other aspect of workability is
cohesiveness. It tells whether
a concrete mixture is plastic, harsh or sticky.
Concrete is required to be plastic which
allows it to be molded and hold a shape when
formed.
 Sticky mix:
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49.  Harsh Mix:
low plasticity
 components tend to segregate
 may have very high or very low water content
 may have low cement content
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50. Includes following stages
 Batching of concrete
 Mixing of concrete
 Transportation of concrete
 Placing of concrete
 Compaction of concrete
 Curing of concrete
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51.  Batching is the process of measuring the
material required for concrete mix by weight
or volume.
Batching is done by two approaches.
 Volume batching
 Weight batching
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52. 52

53.  Volume Batching
Volume batching is done by a typical gauge
box that is known as “farmas” in the field.
The volume of farma is 0.035m3 which is
similar to the volume of 1 bag of cement.
Farma is made of timber, steel or plastic
materials.
 Weight Batching
Weight batching is done manually or semi-
automatically, or fully automatically. Mostly it
is used in Ready mix concrete plants.
This type of batching is mostly used for
large construction.
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54.  Mixing is necessary to make homogeneous
concrete.
 To obtain a good quality of concrete, it is
necessary to do proper mixing of concrete
ingredients. The mixing of concrete depends
on the types of mixing.
 Types:
 Hand mixing
 Machine mixing
 Ready-mix concrete
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55. Hand Mixing:
 In this way mixing of concrete done by the
hands of workers. This type of mixing is used
for small construction work due to high time
consumption. Also the quality of the concrete
we get very less.
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56. Machine Mixing:
 the mixing of concrete done by various types
of machinery. It is used for medium to large
construction work for example 3 to 4 story
building construction.
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57. Ready mix concrete:
 Now a day’s ready mix concrete become most
popular for large construction because it
gives high-quality concrete. Also, it gives the
flexibility to do concreting work at the site
where we can’t able to produce concrete like
the valley, mountains region, etc.
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58.  In valley regions, concrete ingredients like
cement, aggregate, sand, water, and other
materials are not easily available. So we
need to transport material from other
locations which increase the cost of
construction.
 In this type of mixing, concrete mixing is
done in a ready mix concrete plant that is
situated on-site or another site.
 In the case of the RMC plant situated in
another place, the concrete can be
transported by the transit mixer to the
construction site.
 It is economical for large construction.
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59. Ready mix concrete plant Consist the
following parts:
 Batcher (to measure material)
 Conveyor system (to move ingredients of
concrete to the concrete mixer)
 Silos (to store cement)
 Concrete Mixer (To mix concrete)
 Screw Conveyor (to convey cement from
silos to the concrete mixer)
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60. 60

61.  Mortar pan:
A mortar pan is used for small construction work in
which concrete or mortar can be transported by
laborers using a mortar pan.
 Wheel Borrow:
The wheel borrow method of concrete transportation
is suitable for long-distance concrete transportation
on the site. It is majorly used for the construction of
roads, slabs, etc.
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62.  Bucket & Ropeway:
Bucket & ropeway method of concrete
transportation is used to transport concrete in
valley areas.
 Transit mixer:
A transit mixer is suitable for long-distance
concrete transportation. It is used to transport
a large volume of concrete to the construction
site which is situated a long distance away
from the mixing plant.
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63. Skip & Hoist:
 It is used in concreting of
skyscraper building.
Pumps & pipelines:
 Now a day’s this type of concrete transportation is
most popular for concreting work in tall structures. In
this method, concrete is transported through the
pipes by using pumps. In this method, concrete
conveys from a central discharge point to formwork.
Belt conveyors:
 It is used to convey concrete horizontally or inclined
on the construction site
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64. 64

65. Compaction of concrete is a process in which
concrete is compacted by various methods to
remove entrapped air from the concrete and
increase the strength of concrete.
By doing compaction of concrete, concrete
becomes dense, impermeable due to that the
durability of concrete increases.
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66. 66

67. Compaction of concrete done by two ways.
• Hand compaction
• Mechanical compaction
Hand compaction:
Hand compaction of concrete is done by various techniques.
• Roding
• Ramming
• Tamping
Mechanical compaction:
Mechanical compaction is done by various type of vibrating machineries
which are given below.
• Needle vibrator
• Form vibrator
• Table vibrator
• Surface vibrator
67

68.  Immersion or needle vibrator
 Extended or shutter vibrator
 Surface Vibrator
 Vibrating table
68

69. 1. Immersion or needle vibrator
 Internal vibrators, also known as immersion or
concrete needle vibrators are the most common
types of vibrators used on construction sites.
 It comprises a steel tube with an eccentric vibrating
element within (one end closed and rounded). The
poker vibrator machine comprises a steel tube
connected to an electric motor, a diesel engine, or a
gasoline engine via a flexible tube.
 The size of poker ranges from 40 to 100 mm in
diameter. The poker diameter is determined by
taking into account the distance between the
reinforcing bars in the formwork.
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70.  Internal vibrator machine’s needle size ranges from
25 mm to 90 mm, with a minimum of 25 mm and a
maximum of 35 mm used for roof slab casting.
 For the compaction of concrete mass in column
and beam structures, we should utilize a vibrator
machine with 40 mm and 60 mm needles.
 When proposing a strong footing and various
bridge structures, we should use a vibrator
machine with a 75 mm and 90 mm needle to
compact the concrete mass by capturing air gaps
and preventing honeycomb.
 Vibrations from vibrator machines have a frequency
of up to 15000 rpm. However, with an accel, a
range of 3000 to 6000 rpm is advised as a
preferable minimum.
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71. 71

72. 2. External Vibrator
 The external vibrator is also known as shutter
shape vibrator. It includes a base plate. It is used to
compact the surface of precast concrete as well as
the freshly poured concrete. A three-phase
induction motor powers it.
 Its construction is completely closed. It’s also
trustworthy and easy to maintain, with a power
cord made up of four rubber-coated cables. The
casing is usually built of an aluminum alloy casting.
It has a highly efficient lightweight motor structure.
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73.  According to the building pattern, the
machine is secured to the formwork
horizontally or vertically at acceptable
spacing but not exceeding 90 cm in both
directions.
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74. 3. Surface Vibrator
 Surface vibrators are permanently affixed to the
concrete mass. During the screening process, they
vibrate the concrete away from the surface.
 When used in conjunction with concrete with low
water to cement ratio, it is an excellent choice for
the compaction of shallow elements.
 For greater depth than 250 mm of the concrete, we
should not use it. With the help of this machine,
even dry mixes can be compacted successfully.
Surface vibrators include things like pan vibrators
and vibrating screeds.
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75.  It is commonly used for
compacting small slabs,
mending, and fixing
horizontal surfaces such
as pavement slabs. It
spins at a frequency of
around 4000 rpm.
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76. Vibrating Table
 A fast-spinning eccentric weight, in general,
produces In a circular motion,. The system is made
up of two shafts that rotate in opposite directions.
 The table can be subjected to a horizontal
component of vibration that can be neutralized.
Only in the vertical direction is there a simple
harmonic motion.
 There are also some minor positives. Vibrating
tables of high quality powered by an electromagnet
powered by alternating current. The frequency
range reached is between 1,500 and 7000 rpm.
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77.  A table with variable
amplitude should be utilized
for vibrating concrete sections
of various diameters or
laboratory purposes.
Vibrations with varying
frequencies are a bonus. A
vibrating table is a safe and
effective way of compacting
precast concrete.
 The benefit of providing
consistent treatment
electrically or pneumatically
controlled vibrating tables is
particularly beneficial for
precasting work.
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78. Placing of concrete is the process of deposition
of concrete in its required position.
78

79. Placing of concrete is the process of deposition
of concrete in its required position.
Placing of concrete under water is done by
various methods.
1.Placing in de-watered caissons or cofferdams
2. Tremie method
3. Bucket placing
4. Placing in bags/Bagged method
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80. 80

81. Tremie Method:
 A tremie is a watertight pipe, generally 250
mm in diameter, having a funnel-shaped
hopper at its upper end and a loose plug at
the bottom or discharge end as shown in Fig.
 The valve at the discharge end is used to de-
water the tremie and control the distribution
of the concrete.
 The tremie is supported on a working
platform above water level, and to facilitate
the placing it is built up in 1 to 3.5 m section
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82. 82

83. 83
• The concrete is deposited under water
by a bottom opening bucket
• The buckets usually are fitted with a
bottom roller or drop bottom gates
• The bucket is filled with concrete and
its top covered with gunny sack and
lowered slowly
• It is lowered by a crane up to the
bottom surface of the concrete and
then opened either by a suitable
arrangement from the top or by a
diver

84. There are different methods used for curing of
concrete
1. Covering
2. Ponding
3. Immersing In Water
4. Steam Curing
5. Sprinkling
6. Curing With Chemicals
7. Membrane Curing
8. Electrical Curing
9. Curing By Infrared Radiation
84

85. 1. Covering
 The newly laid concrete
surface is covered by
wet gunny bags, which
are wetted periodically.
 This curing method is
suitable for horizontal as
well as vertical and
sloping surfaces.
85

86. 2. Ponding
 Ponding is one of the best
methods for curing of
concrete, mostly practiced
in India.
 In this curing method, the
whole surface is divided
into rectangular or square
enclosures by constructing
small clay or mud bunds
and these enclosures are
filled with water
periodically forming small
ponds.
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87.  Ponding method is suitable for curing
horizontal concrete surfaces such as the
floor, pavements, etc.
 Though this curing method is very good, the
water requirement for this method is very
large, and sometimes mud bunds may be
washed out by water or water may be leaked
through mud bunds.
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88. 3. Immersing In Water
 Pre-cast concrete
members are often cured
by immersing them
underwater.
 This curing method is not
suitable everywhere due
to the lack of water.
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89. 89

90. 5. Sprinkling
 In this concrete curing
method, the concrete
surface is kept wet by
sprinkling water
frequently over the
surface.
 In this case, the water
requirement is very
large, therefore, it is
acceptable for that
place where water is
sufficiently available
for this method.
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91. 6. Curing with Chemical
 In this chemical curing
method, water is
sprinkled over the
surface after adding a
certain amount of
hygroscopic salt such as
NaCl, CaCl, etc. which
absorbs moisture from
the atmosphere.
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92. 7. Membrane Curing
 In the membrane curing method, the concrete
surface is kept covered by a waterproof
membrane such as wax emulsion, bitumen
emulsion, etc.
 The bituminous compounds are black in
colour. The heat absorbed by such substances
is therefore much higher. They end up raising
the concrete surface temperature which is
inappropriate. For this reason, certain non-
black modified compounds are used. These
types of compounds are known as ”Clear
Compounds”, which help to reduce heat
absorption.
92

93.  The membrane prevents the evaporation of
water from the concrete surface.
 In order to obtain the best results, the
membrane is applied after one or two days
of actual water curing.
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94. 8. Electrical Curing
 The electrical curing method is applicable for
cold climate regions. This method is not
preferable in ordinary climate regions.
 In this method, concrete can be cured by
passing an electric current( must be an
alternative current) through the concrete.
Prevention must be taken during curing by the
electrical method.
 As they have many disadvantages, this
method is not much more acceptable for
concrete curing.
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95. 9. Curing By Infrared Radiation
 Infrared radiation is another method for
curing of concrete, which is applicable in very
cold climate regions.
 The infrared radiation method is mostly used
in Russia. It is claimed that this method helps
to get more rapid strength than steam curing.
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96. Types of
Structure
Best Methods for Different Types of Concrete
Structure
Horizontal
members
like floor, roof,
etc.
For horizontal members, ponding is the best-suited
method, other methods like sprinkling, steam curing,
chemical, and membrane Curing are also preferable.
vertical
members like
columns, walls,
etc.
For curing vertical members, covering and sprinkling
are the best-suited methods.
Pre-cast
members
For pre-cast members, steam curing and immersing
in water are the best methods.
Concrete
structure in
very cold
weather
For very cold regions, electrical curing and curing By
infrared radiation method may be used.
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