Every individual aspires to use the best quality products to build their homes. They want to make sure their buildings are suited with the most effective components. The building process is a very challenging and strenuous affair that requires attention. Sometimes small decisions can hugely impact the building’s future.After fixing the design aspects of your dream home, choosing the suitable cement is the most crucial decision. It will determine the quality and strength of the building. So, it is of paramount importance to know how to choose cement that fulfills your desired goals. Generally, a lot of factors are considered before choosing the best cement in Bangladesh. There are a plethora of categories, and each type of cement serves a different purpose. Hence, the right kind of cement should be used depending on the location and objective.
What is Cement?
Cement is one of the essential construction materials. It is produced from processing limestone and other materials. Cement is manufactured at plants where materials are burned in a rotary kiln and ground to a fine powder. Cement’s exquisite property enables it to bond solid matter into a compact mass. So, the final product comes out as a reliable and durable material. Moreover, it can resist corrosion. It is an essential element for building stable structures.Source:Concrete Network
This is the most common type of cement available in Bangladesh. This cement is used worldwide for all types of construction work. OPC is manufactured as a powder by mixing limestone and other raw materials containing argillaceous, calcareous, and gypsum. OPC contains 95% cement clinkers and 5% gypsum. OPC is available in three different grades. The grade numbers imply the strength of the cement that is being used.
33 Grade Cement: OPC 33 grade cement is used in construction projects that do not require high-density concrete and non-RCC (Reinforced Cement Concrete) works. As the grade number suggests, OPC 33 grade can achieve a minimum strength of 33 megapascals (MPa) after a setting of 28 days. However, the 33 grade is no longer used as higher-grade cement is readily available and provides much better durability. Hence 33 grade has become almost obsolete.
43 Grade Cement: OPC 43 grade cement is a widely used variant of OPC. It is ideal for wall plastering works, non-RCC structures, pathways, and projects that demand less concrete density. Similarly, the cement reaches 43 megapascals strength after 28 days of setting. This category can remain unchanged for a long time but is not suitable for RCC works as it has lesser power than the higher-grade variant.
53 Grade Cement: This is the highest grade OPC. This is widely used in RCC works, pre-stressed concrete, and mortars due to its higher density. This category can reach somewhere between 53 to 70 megapascals strength after 28 days of setting. Hence, 53 grade OPC is used wherever support and strength are required.
PPC cement combines 65% to 75% cement clinkers, 15% to 20% fly ash, and 3% to 6% gypsum. PPC cement is cheaper than OPC, and it can reduce the project’s overall cost. Hence, PPC is ideal for people on a tight budget and does not require the high-strength features that OPC provides. Moreover, PPC can also provide a higher degree of fineness, impermeability, corrosion resistance, and chemical resistance. PPC also has a slower rate of heat hydration. PPC is prone to fewer cracks and shows reduced shrinkage over time due to its less hydration heat.Source:McCoy MartAnother essential thing to remember is that PPC takes much longer than OPC to set but can gain more strength over time. So, small-scale construction projects under a limited budget with a reasonable amount of time on hand can use PPC to maximize the efficiency and effectiveness of the project. But PPC cannot provide high density like OPC.Another benefit of using PPC is that it is environmentally friendly. As a result, PPC is being used more in the housing sector. A lower number of PPC bags is necessary to prepare concrete than OPC. PPC is similar to Portland Composite Cement or PCC.
Portland Slag Cement
PSC is another popular cement category used in construction works in coastal regions, sewage, and water treatment plants. It shows excellent corrosion resistance properties making it the best choice to be exposed to sulfate and chloride. Furthermore, it is an ideal choice where structures can get a lot of seawater.
Rapid Hardening Cement
As the name suggests, rapid hardening cement is used where fast-paced construction works are required. This type of cement is ideally used in pavements and any other repair work as it takes less time to achieve strength. This is also suitable for the quick repair of structures.
Super Sulphate Cement
This cement is especially helpful in situations where structures are vulnerable to many chemical attacks. It is used for mass concrete but cannot be mixed with OPC to get higher strength as it can reduce Super Sulphate Cement’s corrosion resistance property. It expands underwater and shrinks while being cured in the air.
This type of cement is used for building structures under running or stagnant water. Its components are similar to OPC but contain fewer gypsum and some aluminum sulfate. Its properties allow it to set within almost five minutes and get hard within 30 minutes.
Hydrophobic Portland Cement
As the name suggests, this type of cement can repel water. It is used for structures in regions that expect higher rainfall. Construction projects undergo chemical coating procedures to repel moisture for buildings. Therefore, it is used to construct tanks, reservoirs, dams, piers, bridges, and swimming pools where portions of structures are permanently submerged underwater.
This type of cement serves to decorate households. Generally, it does not have enough density to support its weight, and it cannot be used in construction works. So, it can be used to fill gaps in floor and wall tiles, ceramic bathroom fixtures, and wall decorations. This cement has a more natural look and can be painted with different colors to match other sections of walls. However, it is more sophisticated than OPC in manufacturing.Choosing the best cement is crucial to the integrity of the construction project. As discussed earlier, each cement category has specific properties suitable for particular cases. To establish a good construction practice, different types of cement must be utilized in a project. However, OPC and PPC can be used interchangeably if best construction practices are followed. But experts always advise using different cement types as per project demands which can ensure the longevity of the construction project.
How to Choose Cement for Ensuring Maximum Durability?
Construction work is a combination of multiple projects going on together. For ensuring a high-quality standard, a building must use different types of cement in its structure. As mentioned earlier, OPC and PPC are the most common cement types used worldwide for construction projects. The use of PPC has risen heavily in recent times as it offers cheaper and more environmentally friendly outcomes. It is now used in columns, beams, roofs, and foundations. PPC cement is ideal for houses, hotels, bridges, dams, airports, etc. Its eco-friendly nature has made it the first choice in building sustainable homes.OPC can also be interchangeably used for PPC. OPC offers higher strength but also at a higher cost. It is widely used in constructing high-rise buildings, roads, dams, bridges, and flyovers, where superior strength and fast setting are necessary.
Staying Alert During Construction Process
It is never a good practice to mix different categories of cement to reduce construction costs. It can lead to degradation and compromise the structural integrity of a building. After choosing the appropriate cement, it should be prepared and used correctly.
How to Choose Cement in Bangladesh?
There is numerous cement brand in Bangladesh. Bangladesh mainly mass-produces two types of cement. They are known as CEM I and CEM II. CEM I is Ordinary Portland Cement, and CEM II is Portland Composite Cement (PCC), similar to Portland Pozzolana Cement (PPC). Before 2003, Bangladesh only produced OPC, but now PCC is widely available in the country and famous due to its lower cost and environmentally friendly features. PCC shows versatility in various construction situations, which has also helped it gain its renowned name. The housing sector uses both OPC and PCC in Bangladesh.Source:The Daily StarMir Cement manufactures both OPC and PCC. The company follows strict rules and regulations in maintaining a supreme standard of the cement it produces to ensure maximum quality.
Frequently Asked Questions (FAQs)
What type of cement should I choose?
Ans: There are different types of cement, and each has its unique property. It would help if you chose the suitable cement according to your work criteria.
Can I use one category of cement for all purposes?
Ans: Yes, but it is not recommended. RCC structures and foundations require high density and higher strength cement, which is an essential part of the integrityof the whole building. Any compromise in this portion can severely hamper the lifespan and rigidity.
How to choose cement that will be best for small-scale house construction?
Ans: It is better to discuss with experts or engineers to understand which cement to use in different building processes. However, PPC or PSC cement is getting popular in the housing sector in BD.