What is the fineness value of cement?

What is the fineness value of cement?

Fineness of Cement Calculation Result: The standard value of fineness of cement should have fineness less than 10 % or fineness of cement should not be more than 10% as per IS Recommendations.

What is the range of fineness of a regular used Portland cement?

Portland cement particles are generally in the range of 1–50 micrometre (μm) while fly ash particles are usually much finer with the average size in bituminous fly ashes being in the range of 7–12 μm.

What is the difference between OPC and PPC cement?

Portland Pozzolana Cement is a variation of Ordinary Portland Cement. Pozzolana materials namely fly ash, volcanic ash, are added to the OPC so that it becomes PPC. PPC is cheaper than OPC. PPC has low initial setting strength compared to OPC but hardens over a period of time with proper curing.

How do you test fineness of cement?

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 the Blaine of cement?

The particle size or fineness of a cement in cm2/g or m2/kg, usually determined from air permeability tests using a device known as a Blaine permeameter. Fineness affects the hydration rate (setting) and the requirements for the amounts of water, retarder, and dispersant.

What are the 5 types of portland cement?

Five types of portland cement are standardized in the United States by the American Society for Testing and Materials (ASTM): ordinary (Type I), modified (Type II), high-early-strength (Type III), low-heat (Type IV), and sulfate-resistant (Type V).

What is the mix ratio for Portland cement?

Normal ratio is 1 part cement, 2 parts sand, and 3 parts gravel (trade the word part for shovel, bucket, or any other measuring device). # Begin adding water to the mixture slowly, mixing continuously until it becomes plastic enough to place in your form.

Where is PPC cement used?

Use of PPC and OPC They can be reliably utilized in the construction of marine structures, masonry mortars and plastering, hydraulic structures. Besides, they are popularly used in mass concreting works, such as dykes, sewage pipes, dams, etc. PPC is also employed in all other applications where OPC is used.

Why do we use 53 grade cement?

Initial Strength OPC 53 cement gains faster strength as water is added in cement and achieves 30% strength in 3 days, 70% in 7 days, and 100 % strength at end of 28 days. Therefore, OPC 53 is the grade of cement that is most used in construction where faster concrete is required.

Is 90 micron a sieve?

All Answers (5) 90 micron sieve is having aperture size 90 micron. To determine fineness of cement 100 gram of cement is taken on sieve screen and sieving operation is done carefully without pressing cement particles on screen. After sieving, the coarser particle left on screen is called residue.

What is free lime in cement?

Free lime (CaO) in clinkers has to be closely monitored to ensure the quality of cement. Excess free lime results in undesirable effects such as volume expansion, increased setting time or reduced strength. The X-ray fluorescence technique (XRF) is used to perform chemical elemental analysis on cement making materials.

How do you test the fineness of cement?

When does fineness of Portland cement affect its strength?

The smaller the particle size, the greater the surface area-to-volume ratio, and thus, the more area available for water-cement interaction per unit volume. The effects of greater fineness on strength are generally seen during the first seven days (PCA, 1988 [1] ).

How is the fineness of cement test done?

The Fineness test of cement is done by sieving cement sample through standard IS sieve. The weight of cement whose particles size greater than 90 microns is determined and the percentage of residue retained cement particle on 90 micron sieve are calculated. This is known as Fineness of cement.

How is the fineness of a sieve determined?

It will be decided by fineness test for cement with the help of IS standard sieve size of 90µm,which define that residue of grain size more than 90 Micron of cement is not retained about more than10% on sieve,The standard cement should have fineness less than 10 % as per IS Recommendations.

How does the fineness of cement affect hydration?

The fineness of cement indirectly impacts the rate of hydration and thus heat of hydration. Now when you mix cement with water a layer is formed around the particles. The smaller the particles, the more the surface area, and the water requirement for hydration reaction.