What is specific gravity and water absorption of fine aggregate, hi guys in this article know about what is specific gravity and water absorption of fine aggregate. as you know bulk density of fine aggregate coarse aggregate and cement and their specific gravity and water absorption capacity have an important role in designing of mix like M20 m25 M30 and so more—–.
This article will help you understanding the specific specific gravity of fine aggregates and their water absorption capacity. Generally sand have different composition containing high amount of silicon dioxide that is known as Quarz which have chemical property to inertness and provide resistance to weathering .And also fine aggregate have some air voids which is permeable to water and also Asphalt content
What is specific gravity and their type
Specific gravity also known as a relative density is the ratio of mass of unit volume of material sample and the mass of same volume of water.
Specific gravity of any sample material describe about their physical nature which is less dense or more dense than water. The material which have specific gravity less than 1 it should be less dense than water and material when put in water it will be float in water.
The material which have specific gravity more than 1 it should be more dense than water and material when put in water it will be sink in water. And if the value of specific gravity of material is 1 then it contents equal volumes to water.
You should also visits:-
1) Gs of sample < 1 it will float in water
2) Gs of sample > 1 it will sink in water
3) Gs of sample = 1 it will float and sink in water
What are different types of specific gravity
1) Apparent specific gravity ( Gsa)
2) bulk specific gravity (Gsb)
3) bulk SSD specific Gravity
4) effective specific gravity
What is Apparent specific gravity
it is denoted by Gsa. And there is two measurement volume and mass of fine aggregate. In volume measurement only includes the volume of fine aggregate particles and it does not include the volume of any water permeable voids. And mass measurement only includes the mass of sand particles.
So Apparent specific gravity is defined as the ratio of the mass of unit volume of impermeable portion of fine aggregate which does not includes permeable pore in fine aggregate to the mass of an equal volume of gas free distilled water at the stated temperature.
What is bulk specific gravity
it is denoted by Gsb. The volume measurement includes volume of fine aggregates particles as well as volume of water permeable voids and mass measurement includes mass of fine aggregates particle as well as mass of water permeable voids present in it.
Generally it is defined as ratio of mass of unit volume of fine particle including water permeable voids to the mass of an equal volume of gas free distilled water at the stated temperature.
What is bulk SSD specific gravity
it is denoted by Gs(SSD) . Volume measurement includes overall volume of fine aggregate particles volume of water and volume of permeable voids.
So it is defined as the ratio of mass of unit volume of fine aggregate including the weight of water within the voids to the mass of equal volume of gas free distilled water at stated temperature
What is effective specific gravity
it is denoted by Gse . Volume measurement containing volume of fine aggregate and volume of voids filled with water minus volume of Asphalt
So it is defined as the ratio of the mass of unit volume of permeable fine aggregate excluding voids permeable to Asphalt to the equal volume of gas free distilled water is stated temperature
Relationship between these types of specific gravity
Gsa > Gse > Gs(SSD) > Gsb
Apparatus required for the test to procedure
There are various types of partners required for the test find specific gravity of fine aggregate and water absorption capacity
1) weighing balance
2) thermo statical controlled oven
4) airtight container
5) glass rod
6) measuring cylinder
7) filter paper
8) enamel tray
9) wash bottle
10) and towel
Specific gravity and water absorption of fine aggregate Test procedure done on SSD condition
1) take about 500 gram of fine aggregate sample weighted in weighing balance in SSD condition which is surface saturated dry condition and their weight is considered as
Weight 1= A ( sample weight) = 500 gms
2) now 500 gram of fine aggregate sample transfer into pyconometer and first field half of pycnometer which distilled water and stiring with the help of glass and after some hour fulfill of Pyconometre with water and their conical shaped screw tightly bounded and there is is 6 mm size of nozzle at the top of screw by the help of wash bottle fulfill the water up to conical nose.
3) wipe out the outer surface of pyconometer with towel after filling with distilled water and weighted it says
Weight 2= B ( mass of fine aggregate water and pycnometer) = 1824 gms
4) now transfer the contents of pyconometer in enamel tray care being is taken to ensure that all the fine aggregate is transferred to enamel tray and rest for some hour for settling of fine aggregate particles
5) again the refill the pycnometer with distilled water to the same level and weighted it says
Weight = C ( weight of pycnometer with water) = 1513 gms
6) the material of fine aggregate with water which was placed in enamel tray was being trained out in cylinder beacker with the help of funnel and filter paper
7) now sample of fine aggregate is placed along with enamel tray in thermo static control oven at temperature of 110 degree Celsius for 24 hours
8) after removing the fine aggregate sample from thermo static control oven first cool it
And weighted and says
Weight 4= D ( weight of oven dry sample) = 496 gms
Calculation of specific gravity and water absorption of fine aggregate
1) calculation of specific gravity in SSD condition
Value of A = 500 gms
Value of B = 1824 gms
Value of C = 1513 gms
Value of D = 496 gms
Specific gravity = D/A_( B_C)
Specific gravity = 496/500_(1824_1513)
Specific gravity = 496/(500_311)
Specific gravity = 496/189= 2.62
Gs( SSD) of fine aggregate = 2.62
2) calculation of Apparent specific gravity
Gsa = D/D_( B_C)
Apparent specific gravity = 496/496_(1824_1513)
Gsa = 496/(496_311)
Apparent specific gravity = 495/185
Apparent specific gravity = 2.69
3) calculation of water absorption capacity of fine aggregate
Absorption =( A_D)/D ×100%
Absorption = (500_496)/496 ×100%
Absorption = 4/496 ×100%
Water absorption = 0.8 %