How do you determine the fineness of cement by air permeability method?
FINENESS OF CEMENT BY BLAINES AIR PERMEABILITY METHOD (IS-4031-PART-2)
- Measuring instruments.
- V = (M1-M2)/D,
- i.e. W = (1-e)ρV.
- or W = 0.500ρV.
- IS:4031(Part-2):1996-Method of physical tests for hydraulic cement(Determination of fineness by Blaine air permeability method)
Which unit is used to measure fineness of cement in Blaine’s apparatus?
square centimeters per gram
The Blaine Fineness Apparatus is used in measuring the fineness of Portland cement in accordance with ASTM and AASHTO standards. The fineness is measured in terms of the specific area of cement expressed as total surface area in square centimeters per gram.
Which of these are methods of testing of fineness of cement?
sieving
Fineness of cement is tested in two ways : (a) By sieving. (b) By determination of specific surface (total surface area of all the particles in one gram of cement) by air-permeability apparatus. Expressed as cm2/gm or m2/kg. Generally Blaine Air permeability apparatus is used.
What is cement fineness?
The fineness of cement is a measure of the size of particles of cement and is expressed in terms of the specific surface area of cement. The fineness of cement is measured as the % weight retained on a 90µm IS sieve over the total weight of the sample.
What is air permeability test of cement?
Blaine Air Permeability Apparatus is used for determining the fineness of Portland Cement measures the specific surface area of fine materials in square centimeters per gram of test sample. By using this apparatus, a quantity of air is drawn through a bed of definite porosity.
What is the fineness of cement?
What is cement fineness test?
The Fineness Test of Cement is done by sieving cement sample through standard IS sieve. The weight cement particle whose size greater than 90 microns is determined and the percentage of retained cement particle are calculated. This is known as the Fineness of cement.
Why fineness test of cement is done?
Fineness test of cement is done to determine the particle size of cement. As, the rule of thumb, the finer the cement particle the best will be the cement and on the other hand the coarser the particle it will not be that good.
What is Blaine fineness?
The fineness of a powdered material, such as cement, as determined by the Blaine apparatus; usually expressed as a surface area in square centimeters per gram.
What is fineness test used for?
The fineness of cement has an important bearing on the rate of hydration and hence on the rate of gain of strength and also on the rate of evolution of heat. Finer cement offers a greater surface area for hydration and hence faster the development of strength. The fineness of grinding has increased over the years.
What is the unit of fineness of cement?
The fineness of cement is represented as cm2 / gram i.e Area/mass. The fineness of cement is measured by sieving it on the standard sieve. The proportion of cement of which the grain sizes are larger than the specified mesh size is thus determined.
How to determine the fineness of cement by Blaines air permeability method?
Place two new filter paper discs on the perforated disc. Fill the cell with mercury. Level the mercury to the top of the cell with a glass plate. Remove the mercury from cell and it, M1.
What are the standard test methods for fineness of?
The calibration of the air permeability apparatus shall be made using the standard reference material. The automated test method shall employ apparatus designed either on the principles of the Blaine air-permeability method or apparatus based on the air-permeability principles of the Lea and Nurse method.
How is the fineness of hydraulic cement determined?
The Blaine Fineness method covers the determination of the fineness of hydraulic cement, using the Blaine air-permeability apparatus, in terms of the specific surface expressed as total surface area in square centimeters per gram, or square meters per kilogram, of cement.
What is the Blaine air permeability apparatus made of?
The Blaine air-permeability apparatus consists essentially of a means of drawing a definite quantity of air through a prepared bed of cement of definite porosity. The permeability cell shall consist of a rigid cylinder, constructed of austenitic stainless steel.
