Introduction of Cement
- Cement is the foremost vital module of engineering construction jobs.
- Concrete is created by blending sand, aggregate, cement & water at a specific proportion.
- The brawn of Concrete is especially attained by the brawn of Cement, i.e. Concrete brawn is directly proportional to cement brawn which in turn decides the brawn of structure.
- Cement is accessible in several grades. The cement grade refers to the cement compressive strength, which implies how much strength cement possesses or bears.
- These cement grades are tested in a standard cube after 28 days of curing.
- As the cement grade ameliorates, its brawn surges.
- Compressive strength is measured in Mega-pascal (Mpa) or in N/mm2.
Introduction of OPC
- Ordinary Portland cement (OPC) is the most utilized cement within the world for generating concrete, mortar, stucco, & non-specialty grouts.
- OPC has 3 grades supported its brawn- 33, 43 & 53 grade.
- OPC is prepared by grinding together OPC Clinker (95–97%) & gypsum (3–5%).
- Compressive Strength of Cement = Applied Load / Unit Area.
Types of Cement Grades
- OPC Grade Cement-
- PPC Grade Cement-
- PSC Grade Cement-
- Super Grade Cement-
1. OPC Grade Cement-
- OPC means Ordinary hydraulic cement could be fully automated & dried during preparation.
2. PPC Grade Cement-
- PPC means Portland Pozzolana Cement could be fully automated & dried during the preparation & contains gypsum & pozzolanic substances. This cement is employed especially in dams & bridges where more resistivity is required.
3. PSC Grade Cement-
- PSC means Portland Slag Cement is prepared by inter-grinding in Portland cement clinker.
4. Super Grade Cement-
- Super grade cement possesses good strength. This kind of advanced cement is generated by limited companies, such as Ultratech, Ramco cement.
- Difference between 33, 43 & 53 Grade Cement.
- According to Indian Codes, OPC Cement can be categorized into 3 Grades, OPC 33, 43 & 53 Grades.
Difference Between 33, 43 & 53 Grade Cement
OPC 33 Grade Cement
- This grade of cement is employed for a general construction job. Due to the rising supply of finer grades of cement, utilization of 33-grade cement has gradually been declined. Of late, it is rarely found.
Properties of OPC 33 Grade Cement
- It achieves a compression strength of 33 megapascals in 28 days of curing.
- It achieves 16 mph in 3 days, 22 mph in 7 days.
- The Cement, which possesses Compressive strength of 33 N/ mm2 after the 28 days when tested (according to Indian Standards at Standard Conditions), is named as 33-Grade Cement.
- Fineness = 300 m2/kg
- 3 days compressive strength = 16 N/mm2
- 7 days compressive strength = 22 N/mm2
- 28 days compressive strength = 33 N/mm2
- It possesses a high range of workability & is principally utilized for masonry & plastering jobs.
- Hydration heat is lower than other grades.
Price of OPC 33 Grade Cement
- The cost price of 33-grade cement is much lower than 43-grade cement.
Uses & Application of OPC 33 Grade Cement
- Vastly employed in plastering job in single-storeyed houses.
- Additionally utilized for the brickwork of walls & tiling jobs.
- Generally utilized for jobs of low compressive strength (Concrete Grade < M20).
- Code of reference- IS Code – IS 269: 1989.
OPC 43 Grade Cement
- OPC 43 is employed for RCC construction, where a grade of concrete is up to M30.
- This cement is employed for plain concrete work & plastering works where setting time isn’t an essential issue.
- It may be an affordable choice over OPC 53 grade cement.
- It additionally has better grinding of clinkers but is inferior to OPC 53.
- This causes it to possess a sloth gain in strength &, additionally, comparative magnesium lack by a difference of -0.01%, which in turn affects the hydration heat.
Properties of OPC 43 Grade Cement
- It achieves a compression strength of 43 mph (megapascals) in 28 days of curing.
- It achieves 23 mpa in 3 days, 33 mpa in 7 days.
- The Cement, which has Compressive strength of 43 N/ mm2 after the 28 days when tested (according to Indian Standards under standard conditions), is named 43-Grade Cement.
- Fineness = 225 m2/kg
- 3 days compressive strength = 23 N/mm2
- 7 days compressive strength = 33 N/mm2
- 28 days compressive strength = 43 N/mm2
- It’s low in chloride content. Hence it doesn’t cause corrosion of steel reinforcement.
- It provides good workability of concrete.
- The initial strength of 43 Grade Cement remains even after 28 days.
- The hydration heat of 43 Grade Cement is medium.
- This supplies a better surface finish to the structures.
- It is moderately sulfate resisting.
Price of OPC 43 Grade Cement
- The cost price of 43-grade cement is beyond 33-grade but not up to 53-grade cement.
Uses of OPC 43 Grade Cement
- Utilized for preparation of Ready Mix Concrete (RMC).
- Utilized for PCC & RCC work (Concrete Grade upto M-30).
- Employed in the development of RCC bridges.
- For the Construction of Silos & Chimneys, it’s additionally utilized.
- Utilized for finishing of buildings, bridges, roads, & water retaining structures.
- Employed in precast items (blocks, tiles, sheets, pipes etc.) & prestressed concrete.
- Employed for non-structural jobs like plastering, flooring & so on.
- Additionally utilized in Ship Construction.
- Utilized in development (concrete upto M30).
- General Civil Engineering construction jobs.
- Utilized in Asbestos products like sheets & pipes.
- Employed in Non-structural works like plastering, flooring etc.
- Code of reference- IS Code – IS 8112: 1989.
OPC 53 Grade Cement
- OPC 53 is employed if greater strength concrete at affordable cement content is required.
- It possesses a quick setting time with respect to 43-grade cement.
- It’s principally utilized for structural purposes, as in reinforced cement concrete.
- It possesses maximum grinding of clinkers property & it is better than grade 43.
- The hydration heat, however, is further supported by magnesium strength which is 6.01% in OPC 53, only 0.01% > OPC 43.
Properties of OPC 53 Grade Cement
- It achieves a compression strength of 53 mpa (megapascals) in 28 days of curing.
- It possesses a quick setting compared to 43-grade cement. 33 Grade achieves 27 mpa in 3 days, 37 mpa in 7 days.
- The Cement, which has Compressive strength of 53 N/mm2
- after the 28 days when tested. (according to Indian Standards at Standard Conditions), is named as 53-Grade Cement.
- Fineness of 53 Grade Cement = 225 m2/kg.
- 3 days compressive strength = 27 N/mm2.
- 7 days compressive strength = 37 N/mm2
- 28 days compressive strength = 53 N/mm2
- It’s a Sulphate resisting cement.
- It’s low in chloride content.
- Low shuttering cost due to early removal.
Price of OPC 53 Grade Cement
- The cost price of 53-grade cement is loftier than 33 & 43-grade cement.
Uses of OPC 53 Grade Cement
- Utilized in making of Railway Sleepers.
- Utilized in pre-stressed girders.
- It achieves early brawn.
- Utilized in industrial buildings blocks, roads, runways & bridges.
- Employed in making of RCC (Concrete Grade >M-25) bridges & prestressed & precast concrete items like blocks, tiles.
- Employed for M25 (& >M25) concrete grades.
- Utilized in the development of all RCC components like a beam, columns, footings & slabs.
- Code of reference- IS Code – IS 12269: 1987.
|S.No.||Grade of Cement||Compressive Strength in 3 days (N/mm2)||Compressive Strength in 7 days (N/mm2)||Compressive Strength in 28 days (N/mm2)|
- With the pop up of new technologies, the manufacturing of high strength cement became gradually possible.
- Of late, there are only a few Companies that prepare 33-grade cement & 43-grade cement.
- When 33 & 43-grade cement isn’t obtainable, Portland pozzolana cement (affordable) can be selected.