Variations among 33 grades, 43 grades and 53 grades of cement
This article shows the variations among 33 grade, 43 grade & 53 grade of cements.
The grades are found in ordinary portland cement & distinguished as per Bureau Of Indian standard & stated in mega pascal i.e. Mpa = N/mm2
Compressive strength is the load for each unit area that is measured in newton & the area is measured in mm2.
The compressive strength is computed by mixing cement, sand and water together, then they are vibrated and cured to produce cubes & they are examined in laboratory at 27 degree celcius after 3 days, 7 days and 28 days.
Cement grade specifies the compressive strength of cement concrete after 28 days of setting.
33 grade cement attains 16 N/mm2 compressive strength in 3 days while 43 grade attains 23 N/mm2 compressive strength and 53 grade attains 27 N/mm2 compressive strength.
33 grade cement attains 22 N/mm2 compressive strength in 7 days while 43 grade attains 33 N/mm2 compressive strength & 53 grade attains 37 N/mm2 compressive strength.
33 grade cement attains 33 N/mm2 compressive strength in 3 days while 43 grade attains 43 N/mm2 compressive strength & 53 grade attains 53 N/mm2 compressive strength.
The strength of 53 grade cement is not raised significantly after 28 days due to initial strength gain whereas 43 and 33 grades of cement keeps to attain strength after 28 days.
In due course, 43 and 33 grades of cement will acquire equivalent ultimate strength similar to 53 grade of cement.
At the time of preliminary setting, 53 grade cement discharges heat of hydration rapidly as compared to 33 & 43 grades of cement. So, the risk of micro cracking is increased.
The price of 33 grade of cement is inexpensive as compared to 43 & 53 grade cement. The price of 43 grade cement ranges from 305 to 325 per 50 kg bag and 365 to 395 for 53 grade of cement.
33 grade is hardly used as it is substituted with PPC & commonly found in concrete structures with low strength under M20 grade.
43 grade is applied for PPC and RCC works where the grade of concrete remains M30. It is suitable for plastering, tiling, brick & stone masonry, flooring & pathways etc as well as finishing of different types of buildings, bridges, culverts, roads, water retaining structures etc.
53 grade is suitable for different RCC structures like footing, column, beam & slabs as well as RCC works where grade of concrete remains M30 and over.
