Showing posts with label Building material. Show all posts
Showing posts with label Building material. Show all posts
PCC Cement IS 1489: 1991
Cement IS 1489: 1991
• PCC Cementis manufactured by opc clinker with latest amendment it is 15 to 35%
• The pozzolonic materials generally used for manufacture of ppc are cacinet clay fly ash
• Fly ash is a waste material generated in the thermal power station when powered coal is used as fuel
• Calcium hydroxide + pozzolona + water - C-S-H gel
• Ppc produces less heat of hydration and offer greater resistance to the attack of aggressive mass of water
than opc
• Gt reducing leaching of calcium hydroxide when used in hydraulic structures
• Gt is generally used in marine and hydraulic structure construction and other mass concrete
construction.
Advantage of PPC
• Costly clinker is replaced by cheaper pozzolonic materials cheaper in cost
• Soluble CaOH is converted into insoluble cementeous products results in improvement permeability
durable for hydraulic structure and marine works
• Its generates reduced heat of hydration and that too at low rate
• Ppc being finer than opc and also due to pozzolonic action it improves pore size distribution and reduce micro crack .
• Fly ash is finer and lower density the bulk volume of 50 kg bag is slightly more than opc gives more volume of mortar than opc.
• PCC Cementis manufactured by opc clinker with latest amendment it is 15 to 35%
• The pozzolonic materials generally used for manufacture of ppc are cacinet clay fly ash
• Fly ash is a waste material generated in the thermal power station when powered coal is used as fuel
• Calcium hydroxide + pozzolona + water - C-S-H gel
• Ppc produces less heat of hydration and offer greater resistance to the attack of aggressive mass of water
than opc
• Gt reducing leaching of calcium hydroxide when used in hydraulic structures
• Gt is generally used in marine and hydraulic structure construction and other mass concrete
construction.
Advantage of PPC
• Costly clinker is replaced by cheaper pozzolonic materials cheaper in cost
• Soluble CaOH is converted into insoluble cementeous products results in improvement permeability
durable for hydraulic structure and marine works
• Its generates reduced heat of hydration and that too at low rate
• Ppc being finer than opc and also due to pozzolonic action it improves pore size distribution and reduce micro crack .
• Fly ash is finer and lower density the bulk volume of 50 kg bag is slightly more than opc gives more volume of mortar than opc.
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Shallow foundation & there types with detail
Foundations may be broadly classified under two heads
Shallow Foundations :A foundation is shallow if its depth is equal to or less than its width.
Deep Foundations : In case of deep foundations, the depth is equal to or greater than its width.
SHALLOW FOUNDATIONS:
From the point of view of design, shallow foundations may be of the following types:
1 Spread footings
2 Combined footings
3 Strap footings
4 Mat foundation
1.Spread footings - Spread footings are those which spread the super-imposed load of wall or column over a larger area. Spread footings support either a column or wall.
Spread footings may be of the following kinds :
Single footing for a column
Stepped footing for a column
Sloped footing for a column
Wall footing without step
Stepped footing for wall
2 Combined footings -Combined Footings a spread footing which supports two or more columns is termed as combined footing. Combined footings are invariably constructed of reinforced concrete. The combined footing for columns will be rectangular in shape if they carry equal Loads. The design of rigid rectangular combined footing should be done in such a way that centre of gravity of column loads coincide with the centroid of the footing area.
If the columns carry unequal loads, the footing is of trapezoidal shape.
Sometimes, It may be required to provide a combined footing for columns and a wall.
The combined footings may be of the following kinds:
Rectangular combined footing
Trapezoidal combined footing
Combined column-wall footings
3 Strap footings - If the independent footings of two columns are connected by a beam, it is called a strap footing. A strap footing may be used where the distance between the columns is so great that a combined trapezoidal footing becomes quite narrow, with high bending moments. In that case, each column is provided with its independent footings and a beam is used to connect the two footings. The strap serves to transfer the column loads on to the soil with equal and uniform soil pressure under both footings.
4 Mat or 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 more economical to use mat or raft foundation. They are also used where the soil mass contains compressible lenses or the soil is sufficiently erratic so that the differential settlement would be difficult to control.
Raft foundation is also used to reduce settlement above highly compressible soils, by making the weight of structure and raft approximately equal to the weight of the soil excavated.
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Shallow Foundations :A foundation is shallow if its depth is equal to or less than its width.
Deep Foundations : In case of deep foundations, the depth is equal to or greater than its width.
SHALLOW FOUNDATIONS:
From the point of view of design, shallow foundations may be of the following types:
1 Spread footings
2 Combined footings
3 Strap footings
4 Mat foundation
1.Spread footings - Spread footings are those which spread the super-imposed load of wall or column over a larger area. Spread footings support either a column or wall.
Spread footings may be of the following kinds :
Single footing for a column
Stepped footing for a column
Sloped footing for a column
Wall footing without step
Stepped footing for wall
 |
| picture credit :BuildingHow |
2 Combined footings -Combined Footings a spread footing which supports two or more columns is termed as combined footing. Combined footings are invariably constructed of reinforced concrete. The combined footing for columns will be rectangular in shape if they carry equal Loads. The design of rigid rectangular combined footing should be done in such a way that centre of gravity of column loads coincide with the centroid of the footing area.
If the columns carry unequal loads, the footing is of trapezoidal shape.
Sometimes, It may be required to provide a combined footing for columns and a wall.
The combined footings may be of the following kinds:
Rectangular combined footing
Trapezoidal combined footing
Combined column-wall footings
 |
| picture credit : Builder's Engineer |
3 Strap footings - If the independent footings of two columns are connected by a beam, it is called a strap footing. A strap footing may be used where the distance between the columns is so great that a combined trapezoidal footing becomes quite narrow, with high bending moments. In that case, each column is provided with its independent footings and a beam is used to connect the two footings. The strap serves to transfer the column loads on to the soil with equal and uniform soil pressure under both footings.
 |
| picture credit : Wikipedia |
4 Mat or 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 more economical to use mat or raft foundation. They are also used where the soil mass contains compressible lenses or the soil is sufficiently erratic so that the differential settlement would be difficult to control.
Raft foundation is also used to reduce settlement above highly compressible soils, by making the weight of structure and raft approximately equal to the weight of the soil excavated.
 |
| picture credit Gharpedia.com |
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Types of foundation
 |
Every building consists of two basic components
1) the super-structure
2) the substructure or foundations.
The super-structure is usually the part of the building which is above ground.The substructure or
foundations is the lower portion of the building, usually located below ground level.
It transmits the load of the super-structure to the sub-soil.
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ROOF
A roof may be defined as the uppermost part of the building, provided as a structural covering, to
CONTENTS
Introduction
Types of roofs
Pitched roofs and their
sketches
Lean – to roof
King Post Truss
Queen post truss
Simple steel Truss
Roof Covering materials: AC
sheets GI sheet
Definition of
ROOF
A roof may be defined as the uppermost part of the building, provided
as a structural covering, to
protect the building from weather (i.e. from rain, sun, wind, etc.).
Some important features of roofs:
protect the building from weather (i.e. from rain, sun, wind, etc.).
Some important features of roofs:
Structurally,
a roof is constructed in the same way as an upper floor, though the shape of
its
upper surface may be different.
Basically, a roof consists of structural elements which support roof coverings.
structural element may be trusses, portals, beams, slabs (with or without beams), shells or
domes.
upper surface may be different.
Basically, a roof consists of structural elements which support roof coverings.
structural element may be trusses, portals, beams, slabs (with or without beams), shells or
domes.
Stairs
A stair is a set of steps leading from one floor to the other. It is provided to afford the means of
ascent and descent between various floors of a building.
 |
| source Lynda.com |
CONTENTS
ØTechnical Terms
ØRequirements of good stair
ØDimension of steps
ØClassification
ØGeometric design of a dog
legged stair case
INTRODUCTION
nA stair is
a set of steps leading from one floor to
the other. It is provided to afford
the means of
ascent and descent between
various floors of a
building.
nThe room or
enclosure of the building, in which
the stair is located is known as stair-case.
n The opening
or space occupied by the stair is
known as a stairway. It should be suitably located
in a building.
nIn a
domestic building the stairs should be
centrally located to provide easy access
to all the
rooms.
nIn public
buildings, stairs should be located near
the entrance. In big buildings, there
can be more
than one stair.
Stairs may be constructed of timber, bricks, stone,
steel or reinforced
cement concrete.
Cement
CONTENTS
Introduction
OPC
Composition of OPC
PP
Slag cement
Hydration
setting time
Introduction
OPC
Composition of OPC
PP
Slag cement
Hydration
setting time
 |
| source :tribune.com.pk |
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Introduction: The natural cement is obtained by burning and crushing the stones containing clay, carbonate
of lime and some amount of carbonate
of magnesia. The clay content in such stones is about 20
to 40 %. The natural cement is brown in colour
and its best variety is known as the Roman Cement. The natural cement resembles the eminent
hydraulic lime. it sets very quickly after addition of water. It is not so
strong as artificial cement and hence it has limited use in practice.The artificial cement is obtained by burning a mixture of specially
selected materials at a very high temperature. The mixture of
ingredients should be intimate and they should be in correct proportion. The calcined
product is known as the clinker. A
small quantity of gypsum is added to the clinker and it is then pulverised
into very fine powder which is known as the cement.
Civil Engineering Questions and Answers
option
1 ) 10%
2) 20%
3) 25%
4) 30%
Q2 King closers are related to
option
1 ) doors and windows
2) king post truss
3) queen post truss
4)brick masonry
Q3 The texture of sandstone is
option
1 ) porphyritic
2) conglomerate
3)vesicular
4)granular crystalline
Q4 A good brick ,when immersed in water bath for 24 hours,should not absorb more than
option
1 )20% of its dry weight
2) 30%of its saturated weight
3) 10% of its dry weight
4) 20% of its saturated weight
Q5 The crushing strength of a good building stone should be atleast
option
1 )50 MPa
2) 100 Mpa
3) 150 Mpa
4) 200 MPa
Q6 The slenderness ratio for masonry walls should not be more than
option
1 ) 50
2) 40
3) 30
4)20
Q7 Bricks are burnt at a temperature range of
option
1 ) 500℃ to 700℃
2) 700℃ to 900℃
3) 900℃ to 1200℃
4)1200℃ to 1500℃
Q8 The minimum compressive strength of first class bricks should be
option
1 ) 5N/mm2
2) 7.5N/mm2
3) 20N/mm2
4)10N/mm2
Q9 The number of bricks required per cubic metre of brick masonry
option
1 ) 400
2) 450
3) 500
4) 550
Q10 When the corner of a bricks is removed along the joining midpoints of adjoining sides ,the
portion left is called
option
1 ) closer
2) squint
3)queen closer
4) king closer
ANSWER
1 ) 10%
2) brick masonry
3) granular crystalline
4) 20% of its dry weight
5)100 Mpa
6) 30
7)900℃ to 1200℃
8)10N/mm2
9)500
10)king closer
Civil Engineering Questions and Answers Part 4
option
1) 10 to 20 %
2)15 to 20 %
3) 20 to 25 %
4) 25 to 30 %
Show
Q2 The approximate ratio between the strength of cement concrete at 7 days and at 28 days is
option
1)3/4
2)2/3
3)1/2
4)1/3
Show
Q3 Modulus of elasticity of M25 concrete as determined by formula of IS :456 is
option
1) 124500 MPa
2) 90125 MPa
3) 28500 MPa
4) 16667 MPa
Show
Q4 General shrinkage in cement concrete is caused by
option
1)carbonation
2) stressed due to external load
3)drying with starting with a stiff consistency
4) drying with starting with a wetter consistency
Q5 The optimum number of revolution over which concrete is to be mixed in a mixer machine is
option
1)10
2)20
3)50
4)100
Q6 As per IS code of practice ,concrete should be cured at
option
1)5 ℃
2)10 ℃
3) 27 ℃
4) 40 ℃
Q7 The ratio of direct tensile strength to that of modulus of rupture of concrete is
option
1) .25
2).5
3).75
4)1.0
Q8 Which one of the following aggregate gives maximum strength in concrete ?
option
1)Rounded aggregate
2) Elongated aggregate
3) Flakey aggregate
4) Cubical
Q9 Which of the following types concrete is most suitable in extreme cold climates
option
1)Air- entrained concrete
2) Ready mix concrete
3) vacuum concrete
4) coarse concrete
Show
Q10 What is the range of fineness modulus of sand which is least suitable for making a good concrete
option
1) 3.5- 4.5
2) 2.9 - 3.2
3) 2.6 -2.9
4) 2.2 -2.6
answer
1)15 to 20 %
2)2/3
3)28500 MPa
4)drying with starting with a wetter consistency
5)20
6) 27 ℃
7).5
8)Cubical
9)Air- entrained concrete
10) 3.5- 4.5
Civil Engineering Questions and Answers Part 3
Q1 . If 'p' is the standard consistency of cement ,the amount of the water used in conducting the initial setting time test on cement is :
option
1) .65 p
2) .85p
3) .6p
4).8p
Q2 . Gypsum is used as an admixture in cement grouts for
option
1)accelerating the setting time
2)retarding the setting time
3)increasing the plasticity
4)reducing the grout shrinkage
Q3.Before testing setting time of cement one should test for
option
1) soundness
2)strength
3)fineness
4)consistency
Q4 The fineness of cement is tested by
option
1) air-content method
2) air-permeability method
3) Le -chatelier apparatus
4)Vicat's apparatus
Q5 For marine works ,the best suited cement is
option
1)low heat portland cement
2)rapid hardening cement
3)ordinary portland cement
4)blast furnace slag cement
Q6 Ultimate strength of cement is influenced by which one of the following ?
option
1)Tricalcium silicate
2)Dicalcium silicate
3)Tricalcium aluminate
4)Tetracalcium alumino-ferrite
Q7 The specific gravity of commonly available ordinary portland cement is
option
1)4.92
2)3.15
3)2.05
4)1.83
Q8 A quick -setting cement has an initial setting time is about
option
1) 50 minutes
2)40 minutes
3)15 minutes
4)5 minutes
Q9 In cements ,generally the increase in strength during a period of 14 days to 28 days is primarily due to
option
1)C3A
2)C2S
3)C3S
4)C4AF
Q10 Soundness test of cement is carried out of determine its
option
1)alumina content
2)iron oxide content
3)free lime content
4) durability under sea water
Answer
1 .85p
2 retarding the setting time
3 consistency
6 Dicalcium silicate
7 3.15
8 5 minutes
9 C3S
1o free lime content
click here to download pdf
option
1) .65 p
2) .85p
3) .6p
4).8p
Q2 . Gypsum is used as an admixture in cement grouts for
option
1)accelerating the setting time
2)retarding the setting time
3)increasing the plasticity
4)reducing the grout shrinkage
Q3.Before testing setting time of cement one should test for
option
1) soundness
2)strength
3)fineness
4)consistency
Q4 The fineness of cement is tested by
option
1) air-content method
2) air-permeability method
3) Le -chatelier apparatus
4)Vicat's apparatus
Q5 For marine works ,the best suited cement is
option
1)low heat portland cement
2)rapid hardening cement
3)ordinary portland cement
4)blast furnace slag cement
Q6 Ultimate strength of cement is influenced by which one of the following ?
option
1)Tricalcium silicate
2)Dicalcium silicate
3)Tricalcium aluminate
4)Tetracalcium alumino-ferrite
Q7 The specific gravity of commonly available ordinary portland cement is
option
1)4.92
2)3.15
3)2.05
4)1.83
Q8 A quick -setting cement has an initial setting time is about
option
1) 50 minutes
2)40 minutes
3)15 minutes
4)5 minutes
Q9 In cements ,generally the increase in strength during a period of 14 days to 28 days is primarily due to
option
1)C3A
2)C2S
3)C3S
4)C4AF
Q10 Soundness test of cement is carried out of determine its
option
1)alumina content
2)iron oxide content
3)free lime content
4) durability under sea water
Answer
1 .85p
2 retarding the setting time
3 consistency
4 air-permeability method
5 blast furnace slag cement6 Dicalcium silicate
7 3.15
8 5 minutes
9 C3S
1o free lime content
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Flow Test
This test is suitable for concrete having high to very high workability .
This test consist of a flow table of diameter 76 cm and metallic mould in the shape of the frustum of the bottom of diameter 25 cm top diameter 17 cm and height 12 cm .
In order to perform this test mould is centred over the table and concrete is filled in it in two layers.Once the mould completely filled it is raised vertically and the table is raised and dropped by 12.5 mm ,15 number of times in 15 second which causes to concrete to spread over the table.
Average diameter of the spread over the table is then measured in atleast 6 directions nearest to 5 mm which is further used to represent the workability in terms of flow percent .That is defined as percentage increase of the average diameter of the spread over the base diameter .
Flow %varies in the range of 0 to 150.
This test consist of a flow table of diameter 76 cm and metallic mould in the shape of the frustum of the bottom of diameter 25 cm top diameter 17 cm and height 12 cm .
 |
| credit ::: Self Consolidating High Performance Concrete :: SCC Self |
Average diameter of the spread over the table is then measured in atleast 6 directions nearest to 5 mm which is further used to represent the workability in terms of flow percent .That is defined as percentage increase of the average diameter of the spread over the base diameter .
Flow %varies in the range of 0 to 150.
Soundness Test of Cement
It is important that no change in the volume of cement take place after it's harding as it significantly affects the durability of the structure in which it is used for the construction .
Unsoundness of cement is due to the presence of lime ,magnesia and sulphur.
Unsoundness due to lime
Unsoundness due to lime is determine using Lechatelier's test which consist of a split cylinder of diameter and height 50mm and indicator the arms of length 165mm .Which are place on either side of split .
In order to perform this test 100 grams of the cement iis guaged with .78P (78% of the water required to prepared cement paste of standard consistency is added ) and the paste form is filled the split cylinder and covered from top and bottom with the help of glass plates .
The entire assembly is then immersed in water having the temperature 27 to 30 degree celsius
for 24 hours .
The assembly is removed and distance between the indicator arms is noted .(x)
The assembly is again immersed in the water temperature of which is increased upto its boiling point within 25 to 30 minutes and it maintain for next 5 hours.
The assembly is removed from the water allow to cool off and distance between the indicator arms is again noted (y).
For OPC the difference between the two reading should not exceed 12mm.
Unsoundness Due To Magnesia
Unsoundness due to magnesia is determined using autoclave test which is sensitive to both volume changes due to lime and magnesia.
In this test a block of 25x25x282 mm is prepared and is placed in the autoclave steam pressure of 21 kg/cm^2 is attained within 1 hour and is maintained for next three hours .
The mould is then removed from the autoclave and is tested for its size .
For OPC increase in size of any side must not exceed 0.8%.
Watch Video
Unsoundness of cement is due to the presence of lime ,magnesia and sulphur.
Unsoundness due to lime
Unsoundness due to lime is determine using Lechatelier's test which consist of a split cylinder of diameter and height 50mm and indicator the arms of length 165mm .Which are place on either side of split .
In order to perform this test 100 grams of the cement iis guaged with .78P (78% of the water required to prepared cement paste of standard consistency is added ) and the paste form is filled the split cylinder and covered from top and bottom with the help of glass plates .
The entire assembly is then immersed in water having the temperature 27 to 30 degree celsius
for 24 hours .
The assembly is removed and distance between the indicator arms is noted .(x)
The assembly is again immersed in the water temperature of which is increased upto its boiling point within 25 to 30 minutes and it maintain for next 5 hours.
The assembly is removed from the water allow to cool off and distance between the indicator arms is again noted (y).
For OPC the difference between the two reading should not exceed 12mm.
 |
| credit Civil Engineering Test |
Unsoundness Due To Magnesia
Unsoundness due to magnesia is determined using autoclave test which is sensitive to both volume changes due to lime and magnesia.
In this test a block of 25x25x282 mm is prepared and is placed in the autoclave steam pressure of 21 kg/cm^2 is attained within 1 hour and is maintained for next three hours .
The mould is then removed from the autoclave and is tested for its size .
For OPC increase in size of any side must not exceed 0.8%.
Watch Video
Setting Time Test Of Cement
Setting time of the cement is tested in order to check its deterioration due to storage .
Setting time of the cement is further referred as initial setting time and final setting time .
Initial Setting Time Test
Initial setting time test is regarded as the time which is measured from the instant water is added into the cement upto the time it starts loosing its plasticity .For OPC initial setting time is approximately 30 minutes .
In order to perform this test 500 gm of cement is guaged with .85P (i.e. 85% of the water required to prepare the cement paste of standard consistency is used ) and the paste formed is filled in the mould .
Initial setting time is taken as the time in which square needle of size 1 mm penetrates into the mould upto depth of 33 to 35 mm from the top .
Final Setting Time Test
Final setting time is regarded as the time which is measured from the instant water is added into the cement upto the time it completely looses it's plasticity and attain sufficient firmness.
In order to find the final setting time mould is prepared same as above .
Final setting time is taken as the time in which needle at the centre of the annural collar is able to make the impression over the mould but annular collar fails to do so.
For opc final setting time is approximately 10 hours.
Setting time of the cement is further referred as initial setting time and final setting time .
 |
| source :CivilArc |
Initial Setting Time Test
Initial setting time test is regarded as the time which is measured from the instant water is added into the cement upto the time it starts loosing its plasticity .For OPC initial setting time is approximately 30 minutes .
In order to perform this test 500 gm of cement is guaged with .85P (i.e. 85% of the water required to prepare the cement paste of standard consistency is used ) and the paste formed is filled in the mould .
Initial setting time is taken as the time in which square needle of size 1 mm penetrates into the mould upto depth of 33 to 35 mm from the top .
Final Setting Time Test
Final setting time is regarded as the time which is measured from the instant water is added into the cement upto the time it completely looses it's plasticity and attain sufficient firmness.
In order to find the final setting time mould is prepared same as above .
Final setting time is taken as the time in which needle at the centre of the annural collar is able to make the impression over the mould but annular collar fails to do so.
For opc final setting time is approximately 10 hours.
Vee Bee Consistometer Test
This test is suitable for the concrete
having low to very low workability .
This is a good laboratory test to measure indirectly the workability of
concrete .
In this test consist of a metallic mould in the shape of frustum which placed
over the vibrating table .
Concrete to be tested is filled in the mould in two layers and when it is
completely filled mould is removed along with the sub
-sequential initiation of the vibration.
Time required to concrete to assume the cylindrical shape is then noted which is referred as Vee Bee degree and is used to represent the workability of the concrete .
Ultrasonic pulse velocity test
Ultrasonic pulse velocity test identify the quality of concrete.It is Non Destructive test.
The principle of this test is based upon the fact that the velocity in solids .Depends upon the modulus of elasticity and density of solid.
The apparatus of this test consist of a transmitter and receiver.
Transmitter is used to generate the pulse of ultrasonic frequency i.e. detected by the receiver placed on the face of the specimen.
The time required by the pulse to travel through the known distance in the specimen is noted which is further used to calculate the velocity of the pulse is related with the quality of concrete under the test .
Result of this test is depends upon several factors as:
Smoothness of the surface under the test.
Temperature of the specimen .
Reinforcement used in the specimen
The principle of this test is based upon the fact that the velocity in solids .Depends upon the modulus of elasticity and density of solid.
The apparatus of this test consist of a transmitter and receiver.
 |
| source :IndiaMART |
Transmitter is used to generate the pulse of ultrasonic frequency i.e. detected by the receiver placed on the face of the specimen.
The time required by the pulse to travel through the known distance in the specimen is noted which is further used to calculate the velocity of the pulse is related with the quality of concrete under the test .
Result of this test is depends upon several factors as:
Smoothness of the surface under the test.
Temperature of the specimen .
Reinforcement used in the specimen
Schmidt Rebound Hammer Test
Rebound hammer test is conducted to find out the compressive strength of concrete. Rebound hammer consist of a spring control mass that slides over the plunger in tubular casing .When the hammer is pressed against the concrete surface to be tested ,and retards against the force of the spring carrying along the rider with it .Movement of which is noted over the scale and is referred as rebound number .Which is further used to indicate the strength of the concrete .
The result of this test depends upon the several factors as,
Smoothness of the surface under the test .
Age of the specimen.
Internal and external moisture condition.
Size ,shape and rigidity of specimen.
Types of coarse aggregate and mould used.
Types of cements used .
Age of the specimen.
Internal and external moisture condition.
Size ,shape and rigidity of specimen.
Types of coarse aggregate and mould used.
Types of cements used .
It depends on the angle on which the rebound hammer is placed to do the test .
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